United Airlines flight 2408 was scheduled to depart DIA at 5:58 p.m. Sunday, . But passengers exited the plane down airstairs soon after the flight left the Denver airport gate, before the plane took off, United spokesperson Russell Carlton wrote in an email to The Denver Post.

“The aircraft was screened and cleared, and passengers returned to the gate where we provided them with food and water,” Carlton said.

DIA staff and the Denver Police Department both responded to the reported bomb threat, an airport spokesperson confirmed.

Denver law enforcement is working with the FBI to investigate the threat, according to the police department. No additional information about the bomb threat was available on Monday.

“Any threat or hoax threat can potentially be a federal crime, including threats to critical infrastructure such as airport operations,” FBI Denver Public Affairs Officer Vikki Migoya said. “No dangerous materials were located on the aircraft. The investigation into the source of the threat is ongoing.”

None of the 200 passengers or seven United crew members was injured. The plane safely left for the Washington Dulles International Airport at 11:33 p.m. Sunday, Carlton said — nearly six hours after its scheduled departure time.

This is a developing story and may be updated.

Airlines reported 794 flight delays and 30 canceled flights as of 8 p.m., according to the flight tracking site .

Departing planes were sprayed with deicing fluid for most of the day, which wrapped up before 5 p.m., according to the n.

Flight delays at DIA included 242 delays on Southwest Airlines, 225 delays on United Airlines and 189 delays on SkyWest, according to FlightAware. SkyWest canceled 16 flights, followed by Southwest with five cancellations, Lufthansa with four, American Airlines with three and United and Frontier with one canceled flight each.

Cold weather is expected to linger overnight, with thermometers expected to drop to 18 degrees, according to the National Weather Service.

On Monday, local leaders in Superior are set to discuss whether the town, along with Boulder County, should try to bring the so-far unsuccessful public nuisance lawsuit they filed against the airport two years ago to the Colorado Supreme Court.

“This is the issue I hear from my residents, day in and day out,” Superior Mayor Mark Lacis said. “People are concerned about the noise and people are concerned about the lead pollution.”

Things haven’t gone the way of the town or county in the legal scrum so far. A Boulder County District Court judge ruled that plane noise and aircraft exhaust were solely the province of the federal government to regulate through the Federal Aviation Administration. Last month, the the lower court’s ruling, while keeping a window of hope open for the plaintiffs.

Noise issues are under the FAA’s jurisdiction, it concluded, but the lead contamination issue needs another look at the district court level.

“We’re not trying to tell the airport how to operate,” Lacis said. “All we filed in our lawsuit was an allegation that this is a public nuisance. Courts have long had the power to address nuisances.”

The Superior Town Council’s Monday discussion is set to happen behind closed doors in an executive session, since it’s a legal matter.

The nuisance factor at Rocky Mountain airport has been all too real for Greg Tan, a nearly 20-year resident of Superior’s Rock Creek neighborhood. The community sits under the flight path of a seemingly endless daily parade of planes — many of them flight school training runs — coming from the airport just to the south.

“All of these flights taking off are going right over my house,” Tan said. “If I’m working from home, I have to put on noise-cancelling headphones or a white noise machine.”

Airport spokesperson Sydny Boyd didn’t answer specific questions submitted by The Denver Post for this story. In a statement, Boyd said the 66-year-old airport, which is owned by Jefferson County, “remains focused on initiatives that support safe operations and continued community compatibility.”

Boyd cited the airport’s voluntary noise-abatement program, the introduction of unleaded aviation fuel and its participation in an FAA-guided noise study as measures the facility has taken in recent years to address complaints.

“RMMA will continue working with stakeholders and regulatory partners as these efforts move forward,” she wrote.

In the meantime, Tan has formed an attachment to the wind that often whips through his neighborhood — since it curtails flight activity, which can often go on until 11 p.m.

“I tell you, I used to hate the wind,” he said. “But now I’d rather take the wind than the noise.”

Increasing activity at airport

Tan is convinced that Rocky Mountain airport could do better if it wanted to. For the first 15 years he lived in Rock Creek, he wasn’t bothered by the nearby airport.

“There wasn’t an issue because there wasn’t as much activity as there has been in the last three, four, five years,” he said.

Takeoffs and landings have exploded at the airport over the last decade.  show airport operations leapt from nearly 150,000 operations in 2016 to nearly double that number in 2023, the most recent year for which the county provides data on its website.

In the airport’s , the county reported that takeoffs and landings at the airport jumped from approximately 282,000 in 2023 to nearly 295,000 in 2024. And with that increase, noise complaints rose from around 5,000 in 2023 to nearly 11,400 the following year.

The lion’s share of the 2024 complaints — around 69% — came from Superior. And according to the noise report, nearly all the complaints centered on prop planes, which are popular aircraft with flight schools.

Tim Sitz, a 25-year resident of Rock Creek, said the frequency of planes flying over his house can sometimes reach as many as two or three in a minute.

“In the summer, we sleep in an internal bedroom to avoid the noise,” he said. “We don’t enjoy our backyard.”

Jefferson County, he surmised, can turn a blind eye to nearby community concerns because the airport is perched in the extreme northeast corner of the county, from where it sends the majority of its air traffic over Broomfield and Boulder counties.

“Superior and Boulder County are impacted, but Jefferson County largely is not,” Sitz said.

In Boulder County and Superior’s 2024 lawsuit, they claimed that flight school “touch-and-go” operations at the airport — during which a plane momentarily lands before taking off again without stopping or leaving the runway — are done under maximum power and at a lower altitude than typical takeoffs.

The result: “maximum lead and noise exposure” for those below, the lawsuit says.

Last June, the FAA led the nation in “potentially significant events, which include both runway incursions and airborne safety incidents.” That prompted a letter five months later sent by to Jefferson County, the FAA and , pleading for changes.

“Under federal and state law, (Jefferson County) has both the authority and the obligation to mitigate noise, pollution, and safety risks,” the letter reads. “Yet the county has repeatedly refused to act — rejecting proposals for curfews, landing fees, and operational limits while dismissing well-documented community health impacts.”

The coalition is made up of Boulder County, Boulder, Broomfield, Lafayette, Longmont, Louisville, Westminster, Erie and Superior.

‘We’re going to make progress’

The March 12 appeals court decision made it clear that state courts have no authority to compel operational changes at airports — that authority rests singularly with the FAA.

But the court said Rocky Mountain airport could make adjustments to mitigate noise and emissions voluntarily under a “proprietor’s exception” in the law.

“We therefore assume, without deciding, that Jefferson County has the authority as the airport proprietor to prohibit touch-and-go operations if it chooses to do so,” the court ruled.

Lacis said the proprietor’s exception calls into question what has long been Jefferson County’s explanation for why it can’t make adjustments: The federal government has tied its hands.

“The county and the airport have long said, ‘We would love to help you, but our hands are tied by federal law,’ ” he said. “The argument they’ve been making has been dismissed by the appeals court.”

While neither the county nor the airport would answer The Post’s questions about taking voluntary measures to reduce aircraft activity and bring relief to neighbors, lawyers for Jefferson County argued in an October case filing that doing so was no easy feat for the airport.

Rocky Mountain airport, the lawyers argued, is “subject to comprehensive regulation by the FAA through the terms of its grant agreements.” That includes making the airport “available for public use on reasonable conditions and without unjust discrimination.”

“Restrictions on touch-and-go operations are expressly subject to this requirement,” the motion stated.

Regardless of the legal twists and turns, Lacis said the fight was not over. His constituents have suffered too much, he said, and he and other local officials aren’t ready to fold.

“I’m optimistic that we’re going to make progress,” he said. “We wouldn’t be continuing the fight if we didn’t think there was progress to be made.”

FAA officials ordered the ground stop at 3:49 p.m. and lifted it at approximately 5 p.m., according to an agency alert.

Weather sensors at DIA recorded gusts as high as 32 mph on Saturday afternoon, with sustained wind speeds reaching 25 mph, according to the

Airlines reported 212 and three canceled flights as of 5:55 p.m., according to the flight tracking site FlightAware, including 74 delayed flights on Southwest Airlines, 54 delayed flights on United and 48 delayed flights on SkyWest.

One person was injured and a plane suffered “substantial” damage when a United Airlines flight collided with two de-icing trucks at Denver International Airport in March after taxiing without clearance, according to investigators.

The United plane was parked on a de-icing pad when the flight crew heard what they believed to be the de-icing crew wrapping up the task and debriefing, according to a preliminary report from the National Transportation Safety Board.

The flight crew conducted all post-de-icing checks and received clearance to taxi from air traffic control, the report stated. However, when they started to move, they hit the de-icing trucks, pushing at least one onto its side. At that time, the flight crew was informed by the de-icing team that they had not been cleared to exit the pad and that the plane had hit the trucks, according to the report.

United Airlines initially reported that a de-icing truck had hit the plane.

One truck driver sustained minor injuries in the March 6 collision, which happened at about 10:24 a.m. None of the 136 people on board the Nashville-bound United plane — including pilots, flight attendants and passengers — were injured, according to the report.

The United plane, a Boeing 737, suffered “substantial” damage to the wings, which hit the trucks, according to the preliminary report.

Federal transportation officials said the investigation remains ongoing and involves NTSB specialists, the Federal Aviation Administration and United Airlines.

Re: “Agents helping with airport security,” March 24 news story

The TSA officers who have remained on the job through the asinine shutdown of Homeland Security should be offered a substantial bonus once the shutdown is over. Maybe delay bombings in Iran for one day and use those funds to reward the TSA officers.

Alan Aldrich, Thornton

These government shutdowns continue to be problematic and affect all of us. They are now the standard for our elected officials. Our government employees, such as TSA, should not have to look for other jobs because our elected officials aren’t interested in compromise.

I have 3 suggestions for laws Congress should pass.

1. When a shutdown occurs, it’s only Congress members who don’t get paid.

2. When the government shutdown is over, Congress doesn’t get back pay.

3. Congress needs to have term limits: Two terms in the Senate and three or four terms in the House. This would be on par with many state legislative bodies.

Alan P. Aboaf, Centennial

Religion spawns division and wars

Something not mentioned about the current wars is that they are largely religious in nature. That should be a warning for us. Religions and their gods do not get along. Even within faiths, the interpretation of the sacred books can vary. Protestants in the United States have many denominations. Islam has two major sects that are often in conflict.

It was with good cause that the writers of our Constitution included the separation of church and state. Once a religion gains ascendance, it creates a horrible blood-rendering state. There are too many examples of religion trying to control all of us, and only for their ends, not ours.

You see the pictures of bowed heads, hands on the president¶¶Ňőap shoulders in the Oval Office and the other worldly atmosphere in the gaudy room. These are the people urging greater wars so as to cause the return of their god. They also intend to strangle us with their laws and beliefs: no abortions, the ten commandments in every classroom, and a Secretary of “War” who uses scripture to justify the killing of thousands.

When asked what was meant by the First Amendment regarding religion, President Thomas Jefferson referred to “a wall.” Total separation.

Religion should be banned from public and governmental places and ceremonies, and taxed as the businesses they are.

As an atheist, there is a verse in the New Testament that I think all religious people should follow. It is Matthew 6:6. In brief, it says those who wish to pray should go into their closets and close the doors.

Mack Hitch, Sterling

The Cuban leaders aren’t suffering with the people

We hear a lot of wailing and moaning these days about how much the Cuban people are suffering: food shortages, medicine shortages, energy shortages, blackouts. It seems to never end.

However, I’m sure the Cuban Communist ruling elite are not suffering. Like all communist dictatorships, and all dictatorships in general, I’m sure the ruling elite have all the food, medicine, energy and lighting they want.

It is too bad for the Cuban people that the communist rulers disarmed the populace after the revolution ended in January of 1959. Just imagine how things would be different for the Cuban people if they had the means of securing a government that was for the people and of the people, rather than a hereditary communist (ie, Castro-centric) dictatorship.

Richard D. VanOrsdale, Broomfield

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Security at DIA over the past two weeks averaged 12 minutes, according to airport records. Travelers never waited longer than 35 minutes, and often got through in less than 10 minutes, airport officials said this week.

That compares with chaos at other airports around the country, where lengthy wait lines delayed travelers for hours. TSA officers have been forced to work without pay for weeks as the partial government shutdown, which started Jan. 31, drags on, leading to short staffing. The long lines prompted the Trump administration to deploy Immigration and Customs Enforcement agents to help the TSA address backups at more than a dozen other airports.

In Denver, a $2.1 billion overhaul of the signature white tent-topped main terminal included a security checkpoints makeover. DIA contractors installed 34 security screening lanes using the latest that allow passengers to keep laptops in their bags and facial recognition technology to speed processing. These replaced 42 old-style lanes.

TSA teams can screen 180 to 240 passengers an hour per lane.

DIA’s west-side checkpoint opened in February 2024. The east-side checkpoint opened in August 2025. Before the terminal reconstruction is completed next year, airport officials plan to install another 12 screening lanes.

After investing $60 million in the equipment for the two new checkpoints, DIA donated it to TSA along with manufacturer warranty, maintenance, and support services, officials said this week in an emailed statement.

DIA made “significant investments in its checkpoint technology, which enhances the experience for every traveler passing through our airport,” officials said. “However, these improvements do not diminish the critical role our federal TSA partners play in keeping operations smooth and secure.”

TSA officials did not respond to questions.

During the shutdown, DIA last week struggled to deal with an unexpected Xcel Energy power outage that caused havoc for hundreds of travelers. But airport officials reported that “TSA workers are showing up to work at DIA.”

DIA rallied public support, launching a donations campaign that has brought in more than 2,759 grocery and gas gift cards to help security officers working without pay handle daily living expenses. “We are grateful to the TSA employees who are continuing to come to work to maintain normal operations.”

The officers were not making arrests or screening passengers. The Trump administration vaguely said they would supplement Transportation Security Administration staffing at certain airports. But after a year of intensified immigration enforcement and protests in cities across the country, their appearance at airport checkpoints has unsettled some travelers and raised new questions about how far their presence might extend.

On Monday, Associated Press journalists observed Immigration and Customs Enforcement officers and agents patrolling terminals and lingering near long lines of passengers at Hartsfield–Jackson Atlanta International Airport, John F. Kennedy International Airport in New York, Newark Liberty International Airport in New Jersey, George Bush Intercontinental Airport in Houston and Louis Armstrong International Airport outside New Orleans.

A handful of other airports — including Phoenix’s Sky Harbor International and William P. Hobby Airport in Houston — also confirmed ICE would be on site.

Officials at Denver International Airport said in a statement Monday that security screening was operating normally and that “we have not received any communication indicating that ICE agents will be staffing our checkpoints.” DIA was not on a where deployments of federal immigration agents were expected Monday.

Wait times at the Denver airport’s security checkpoints have not been as lengthy as the hours-long delays seen at some other airports during the shutdown. At various points Monday, security wait times at DIA’s new East and West checkpoints ranged from zero to 20 minutes, according to the .

Officials at ICE’s Denver field office did not respond to The Denver Post’s request for information Monday.

Federal law enforcement officers are a routine presence at international airports. Customs and Border Protection officers screen arriving passengers, and Homeland Security Investigations agents conduct complex criminal inquiries tied to cross-border activity. But immigration agents are rarely visible at TSA checkpoints, the front line of domestic air travel — and their presence there, even in a limited role, stands out.

ICE deployments arrive amid ongoing Washington impasse

Monday’s deployments came as , including from the TSA, have Ěý˛őľ±˛Ôł¦±đĚý last month.

Funding for the department lapsed Feb. 14, as Democrats refused to fund ICE as well as Customs and Border Protection without changes to their operations in the wake of the deaths of Ěý˛ą˛Ô»ĺĚý in Minneapolis. But the stalemate only deepened with Trump rejecting the latest offer, this one from his own Republican party, after a weekend of negotiations.

The White House staff pitched Trump on the idea of funding DHS, except for the immigration operations that have been central to the dispute, according to a person familiar with the situation and granted anonymity to discuss the private talks. Still, Trump rejected that plan and later Sunday escalated his demands that senators also approve the so-called SAVE America Act, a strict proof-of-citizenship voting bill that has essentially no chance in Congress.

The White House on Monday turned down a request from top Democratic negotiator, Sen. Patty Murray of Washington, to meet that morning and continue talks, according to another person granted anonymity to discuss the private conversations.

Democrats are  to federal immigration operations — including policy changes that would require ICE officers to get a warrant from a judge before forcefully entering homes, the removal of masks and clear identifying information on uniforms.

Unlike many recent immigration operations in U.S. cities, where federal agents have often worn face coverings, ICE officers at airports Monday appeared to be largely not masked — following an earlier direction by Trump.

Fears that the deployments will heighten tension

Some fear that positioning federal immigration officers at security checkpoints will only escalate tensions. Union leaders representing aviation workers stressed that ICE officers don’t have the same training and expertise as TSA workers — and the presence of federal immigration officers could also put some travelers on edge.

Everett Kelley, national president of the American Federation of Government Employees — which represents TSA officers — said in a statement that his members “deserve to be paid, not replaced by untrained, armed agents who have shown how dangerous they can be.”

Whether ICE will have a more sweeping role beyond watching long lines and patrolling terminals has yet to be seen. On Sunday, Trump said federal immigration officers could assist TSA by guarding exit lanes or checking passenger IDs — and the president has since suggested he could deploy the National Guard at airports, too.

ICE and TSA have been “working together so far very well,” Trump said at a Monday public safety roundtable in Memphis. Still, he said he would “bring out the National Guard” if more personnel is needed.

Long wait times persisted at some major hubs Monday.

Atlanta’s Hartsfield–Jackson, for example, is still urging passengers to allow at least four hours for both domestic and international screenings. The check-in line for departing passengers was so long Monday that it snaked from the TSA screening area to the atrium, through the baggage claim and out the entrance doors with people in back of the line waiting outside. But ICE agents were not seen checking IDs or otherwise interacting with passengers.

“I may miss my flight that¶¶Ňőap in one hour,” said Jeffrey Lewis, who was waiting in line Monday hoping to catch his flight from Atlanta to Phoenix. “I think that the government is full of it. I really do.”

Beyond TSA operations, many travelers on the East Coast faced additional disruptions  that killed two people and injured dozens of others on the runway of New York’s LaGuardia Airport. LaGuardia was  as air traffic was diverted for much of Monday.

TSA workers have been going without pay

After weeks of missed paychecks, many TSA agents have called in sick — or  — as financial strains pile up. The  have forced some airports to close checkpoints at times, with  for travelers.

TSA callout rates climbed over the weekend. Nationwide on Sunday, 11.8% of TSA agents missed work — the highest rate of the shutdown so far — with more than 3,450 officers calling out, according to DHS. More than 400 officers have quit during the shutdown, the department said.

Some have accused the government of using TSA workers as pawns in the ongoing budget fight. And aviation unions have raised additional safety concerns in light of the Trump administration’s deployment of federal immigration officers.

“This latest threat of ICE invasion at the airports is another distraction from solutions that protect Americans,” a coalition of unions representing aviation workers — including the Association of Flight Attendants-CWA and International Association of Machinists and Aerospace Workers — said in a Sunday statement. Transportation security officers “can’t simply be replaced” by federal immigration officers, they noted, adding that ICE’s presence and potential attempts to question passengers about immigration status may also “distract them from ensuring airport security.”

The unions called for TSA workers to be paid immediately — noting that, in contrast, ICE officers are among DHS workers who have continued to see paychecks as the partial shutdown drags on.

While routine funding that is used to pay TSA agents has lapsed, ICE and other immigration enforcement operations are funded with personnel receiving paychecks thanks to Trump’s big tax cuts bill that became law last year. It ballooned the DHS budget for immigration detention and deportation by billions.

Associated Press journalists Lisa Mascaro, Seung Min Kim, Tia Goldenberg, and Collin Binkley in Washington; Emilie Megnien and Mike Stewart in Atlanta; Stephen Smith in New Orleans; Russ Bynum in Savannah, Georgia, and Rio Yamat in Las Vegas contributed to this report.

The El Paso County Sheriff’s Office reported the crash at 11:09 a.m. and said it happened near Flying View, which is close to the privately owned Springs East Airport near Ellicott and Calhan.

The Federal Aviation Administration is investigating the crash, sheriff’s officials said.

This is a developing story.

Everett Martinez, , alleged in the federal lawsuit brought against the city Wednesday that he repeatedly warned Denver officials that their actions in both the council’s vote against Key Lime Air and the land-swap deal to acquire the Park Hill Golf Course could violate the airport’s agreement to receive funding from the — and put all future grants in jeopardy.

Jon Ewing, a spokesman for Mayor Mike Johnston, called the lawsuit’s allegations “horse(expletive) from a disgruntled employee” and denied any wrongdoing by city officials.

“The city attorney didn’t say the things listed here,” Ewing said. “No one called for a fake investigation on Key Lime. And the Park Hill deal was and is entirely legal and followed all FAA obligations as well as federal law.”

The lawsuit alleges that city officials ignored Martinez’s legal advice and then retaliated against him, culminating in placing him on administrative leave on March 11 with the instruction that he needed to resign by Wednesday or he would be “removed,” according to the 42-page complaint filed in U.S. District Court for the District of Colorado.

Martinez remained on administrative leave Wednesday afternoon, said his attorney, Steven Murray.

The City Council’s Dec. 15 vote to reject Key Lime Air’s request to lease space at DIA because the airline works with ICE drew national attention this month when U.S. Sen. Ted Cruz, R-Texas, called for a review of the airport’s grant funding. He estimated the airport could lose as much as $385 million in grants.

The city was aware that rejecting the contract put at least $90 million in grant funding at risk, Councilwoman Sarah Parady said in December. Martinez claimed he warned top city officials that rejecting Key Lime Air’s contract over ideological concerns — rather than safety issues — would violate the airport’s grant agreement with the FAA and could result in the airport losing access to all of its federal funding.

Two weeks after the vote, the FAA emailed the airport to “express concerns” about the City Council’s vote, according to the lawsuit. A spokeswoman for the airport, Courtney Law, declined to comment on the lawsuit Wednesday.

“…The stated rationale for the lease denial appears to be unrelated to airport operational, safety or capacity considerations and instead is based on opposition to the tenant¶¶Ňőap aeronautical activities,” the FAA’s Dec. 31 letter read, according to the lawsuit.

Ian Gregor, spokesman for the FAA, could not immediately say Wednesday whether the agency was investigating the airport’s compliance with grant funding requirements.

A few days after the FAA’s notice, during a Jan. 6 meeting between and airport leadership, Brown asked airport officials to investigate Key Lime Air for safety concerns, Martinez alleged in the lawsuit.

“If the FAA comes knocking, I want to be able to have it in my back pocket that council was also voting because of safety issues, but that they ran out of time to get talking about that before voting,” the lawsuit alleges Brown said during the meeting.

Melissa Sisneros, spokeswoman for the Denver City Attorney’s Office, declined to comment.

Martinez rejected Brown’s proposal, which he considered to be unethical and illegal, he alleged in the lawsuit.

“It was a fabricated investigation, a fabricated reason,” Murray said. “The city had already acted. This was a cover-your-backside investigation, and he refused to do that.”

The Key Lime Air situation was not the first time Martinez believed the city’s actions put grant money at risk. He also raised concerns that Denver’s land-swap deal to acquire the Park Hill Golf Course violated the FAA’s rules for federal funding, he said in the lawsuit.

In that deal, the city gave 165 acres of airport land to developer Westside Investment Partners in exchange for the 155-acre Park Hill Golf Course. Martinez believed the airport received less than fair market value for the land it gave up, which he believed violated FAA mandates, among other issues with the deal.

Martinez alleged in the lawsuit that one city official instructed him to withhold information from the FAA about the developer receiving the property and instead inform the FAA only that the city and airport were swapping the land. He refused, according to the lawsuit, but it was not clear what information the city and airport initially shared with the FAA.

He additionally alleged that Acting City Attorney Katie McLaughlin called him at 7:09 p.m. Aug. 6 and told him not to keep records of the deal. Martinez immediately called three people to tell them about the call, the lawsuit says, among other allegations.

“Due to the shocking nature of the call, he documented it immediately,” Murray said.

Martinez alleged in the lawsuit that city officials retaliated against him after he raised concerns in the two cases, including by passing him over for a reclassification that would have resulted in a $50,000 raise. He received a poor performance evaluation in January after he filed a complaint with human resources.

“Martinez has not been asked to violate the law or city policy,” said Ewing, the mayor’s spokesman. “He has not been drawn into a conspiracy. What he has done is violate his ethical obligations to the city by taking personal positions that were in opposition to those held by his own client — which is the city and county of Denver — and by disclosing information protected by attorney-client privilege.”

In the lawsuit, Martinez said he considered himself to be an attorney for the airport, not for the city.

“The city went from being, I think, careless and not dotting the i’s and crossing the t’s to at some point just ignoring what he had to say,” Murray said.