TRIPOLI, Libya — Moammar Khadafy’s regime struck back at its opponents with a powerful attack Friday on the closest opposition-held city to Tripoli.
At least 37 people died in fighting and in an explosion at an ammunitions depot in Libya’s rebellious east.
The bloodshed signaled an escalation in efforts by both sides to break the deadlock that has gripped Libya for 18 days — longer than the Egyptian revolt that led to the ouster of President Hosni Mubarak and inspired a wave of protests across the region.
So far, Khadafy has had little success in taking back territory, with several rebel cities repelling assaults and the entire eastern half of the country under rebel control. But the opposition forces have seemed unable to go on the offensive to march on pro-Khadafy areas.
The assault Friday on the rebel city of Zawiya, about 30 miles west of Tripoli, appeared to be the strongest yet by Khadafy’s forces after repeated earlier forays against it were beaten back.
In the morning, troops from the elite Khamis Brigade — named after the Khadafy son who commands it — bombarded the city’s western edges with mortar shells, heavy machine guns, tanks and anti-aircraft weapons, several residents said. By the evening, another brigade had opened a front on the eastern side. Armed Zawiya citizens supported by allied army units were fighting back.
The leader of the rebel forces, Col. Hussein Darbouk, was killed by fire from an anti-aircraft gun, said Alaa al-Zawi, an activist in the city. Darbouk was a colonel in Khadafy’s army who defected with other troops in Zawiya early in the uprising.
A witness in Zawiya’s hospital said at least 18 people were killed and 120 injured.
Libyan state TV reported the attackers had retaken the city. But al-Zawi, the witness and other residents said it remained in rebel hands, with skirmishes continuing after nightfall.
The day’s other fighting took place at Ras Lanouf, a small oil port 380 miles east of Tripoli, just outside the long swath of eastern Libya held by the opposition.
Rebels attacked Ras Lanouf on Friday afternoon, feeling flush with victory after repelling Khadafy forces who attacked them days earlier at Brega, a larger oil facility just to the east. Fighters armed with Kalashnikovs and heavy machine guns were seen streaming in pickup trucks and other vehicles from Brega heading in the direction of Ras Lanouf.
Ahmed al-Zwei, a member of the post-uprising town committee in nearby Ajdabiya, said the rebels were in control of the Ras Lanouf airstrip and oil and gas facilities, and the regime forces had returned to their base at Sirte, a Khadafy stronghold.
To the northeast, hospital officials said at least 17 people were killed in an explosion at an ammunition storage facility at a military base about 20 miles from the rebel stronghold of Benghazi.
The blast destroyed one warehouse in the base and damaged a second, according to an ambulance driver who said he recovered body parts from the scene.
“There were so many people killed. I can’t describe it,” said a resident of Benghazi who gave his name as Abdullah and whose voice was filled with emotion.
Dr. Habib al-Obeidi in Benghazi’s al-Jalaa hospital said the blast also hit a residential area. The cause of the blast was unclear. Al-Obeidi said it apparently was triggered when people went into the storage facility to collect weapons, but others blamed pro-Khadafy saboteurs.
