With escalating hostilities bringing Libya closer to civil war, rebels appeared to hold the city [Zawiyah] after a night of fighting, fending off tanks and artillery vehicles, special forces and regular army troops, and, rebels said, fighter jets.

Rebel leaders in Libya said the latest attacks by Colonel Qaddafi’s supporters smacked of desperation, and the ease with which the assault on Zawiyah, a city with important oil resources just 30 miles from the capital, was repelled raised questions about the ability of the government to muster a serious challenge to the rebels’ growing power…

The first attack took place shortly after midnight, when some pro-Qaddafi soldiers in pickup trucks tried to pass through the city’s eastern gate, Mr. Nasrat said. But they were spotted by rebel sentries who defeated them with help from army and police defectors defending the town. Four soldiers were killed and several captured, with some of the captives readily surrendering their arms and switching sides, he said

Then, in the early evening, several witnesses said, the Qaddafi forces — believed to be led by his son Khamis’s private militia — attacked from both the east and the west. Three pickup trucks tried to enter the narrow city gates from the west, but a rebel-held artillery unit struck one, blowing it up and overturning a second truck, Mr. Nasrat said. Six more pickup trucks tried to breach the eastern gate, he said, but after an exchange of fire the rebels captured two of the trucks and several of the soldiers.