Heavy clashes broke out today between rebels and loyalists fighting for control of Libya's only functioning oil refinery in the western city of Zawiya, as the opposition tried to cut off fuel supplies to the regime's stronghold of Tripoli.
A rebel field commander in Zawiya, Osama Arusi, said the fighting has shut down an oil pipeline to the capital, where a third of Libya's six million people live. The rebels have surrounded the refinery, which supplies oil and gas to the capital.
"The pipeline from Zawiya to Tripoli has been switched off," he said. "The man who is responsible for switching the pipeline off said it is not working."
The Libyan rebels made a dramatic advance on Saturday out of their bases in the western mountains near Tunisia into Zawiya, just 30 miles of Tripoli. They took control of parts of the city of 200,000, and have since been slowly gaining ground in fierce battles with Gaddafi's forces for days.
The rebel advance is tightening the noose around Tripoli. The fighters are closing in on the capital from the west and the south, while Nato controls the seas off the north of Tripoli, which sits on the Mediterranean coast. Hundreds of miles away from the capital, the opposition is in control of most of the eastern half of the country, and has a transitional leadership council in the rebel de facto capital of Benghazi.
The clashes at the refinery began on Tuesday, then opposition fighters pulled out at nightfall and made a new push in daylight.
An oil engineer in the compound said about 100 soldiers loyal to Muammar Gaddafi remained inside. At least several dozen rebel forces are in the area also.
The capture of the 120,000 barrel per day refinery in Zawiya is more a symbolic coup for the rebels, without major impact on Gaddafi's ability to secure fuel, analysts said.
The flow of crude to the refinery from fields in the south-west of Libya had largely been halted since midsummer and the refinery was believed to be running at about one-third of its normal capacity, drawing mainly on crude oil that was in its storage tanks. But Zawiya mostly produced fuel oil, versus gasoline, which Gaddafi was trucking in mainly from Tunisia and, to a lesser extent, Algeria.
On a second front in the civil war, hundreds of miles from Zawiya around the coastal town of Brega in the east, rebels clashed with Gaddafi troops for control of the town's refinery.