SAN BERNARDINO, Calif. — Authorities on Thursday were still trying to establish a motive for the deadliest U.S. mass shooting in nearly three years, even as they revealed that the two attackers had amassed a large stockpile of explosives and ammunition.
The rampage killed 14 people, wounded 21 and locked down a swath of Southern California for much of the day Wednesday as investigators scrambled to determine whether they were looking at a terrorist attack or an extremely unusual and lethal case of workplace violence.
The killers were a young husband and wife who welcomed the birth of a daughter just six months ago and showed no outward sign of Islamist radicalization, psychological distress or a desire for mayhem. The couple were slain in a wild police shootout on a residential street four hours after the massacre.
The FBI, which has authority to investigate potential terrorism, announced Thursday that it had taken over the investigation. Authorities were carefully picking through three crime scenes: the Inland Regional Center, where the mass shooting occurred; the San Bernardino street where the couple died in the gun battle with police; and the couple’s rented home in Redlands, Calif., where robots helped investigators root out an arsenal of pipe bombs and thousands of bullets.
Police identified the shooters as Syed Rizwan Farook, 28, a county health worker born in Chicago, and Tashfeen Malik, 27, his Pakistani wife, who was in the United States on a visa.
Farook, who had a college degree in environmental health and a steady job as a health inspector, traveled to Saudi Arabia and Pakistan last year and returned with Malik, whom he had met online. They were married in the United States, police said.
Authorities have said the two were not on any watch lists. A senior U.S. law enforcement official said Farook was in contact with persons of interest with possible ties to terrorism but that these were not “substantial” contacts.
Farook’s supervisor, Amanda Adair, who went to college with him at California State University at San Bernardino, said he “got along with everybody, but he kept his distance.” She said she “can’t imagine (the shooting) was about work” and that she had no inkling that Farook had the capacity for such violence.
Without a firmly established motive, authorities Thursday said they could not determine whether they were dealing with terrorists, a disgruntled worker who had enlisted his wife in his cause or some kind of hybrid scenario.
“We do not yet know the motive,” David Bowdich, assistant director in charge of the FBI’s Los Angeles office, said at a news conference. “It would be irresponsible and premature for me to call this terrorism.”
The case doesn’t fit any familiar template. If it was terrorism, why would the shooters target co-workers in a small city that many Americans couldn’t find on a map, rather than some more spectacular target? If it was workplace violence, why build up an arsenal of bullets and pipe bombs?
“It is possible this was terrorist-related, but we don’t know,” President Barack Obama said Thursday in somber remarks in the Oval Office. “It is also possible this was workplace-related.”
Mark Pitcavage, director of the Center on Extremism for the Anti-Defamation League, said that “based on what is known now about the case, it certainly is unusual and does not fit neatly into any of the traditional models of violence that we’re familiar with.”
Authorities said the two had left behind remarkably little in the way of a digital record — no apparent criminal record, no Facebook page, no Twitter account.
