Rebels fought into the city of Zawiyah, just 30 miles from Tripoli, on Saturday. They now say they control most of the city, including the center, though fighting there is reportedly continuing.

They also say they have cut off the road leading to Tunisia, which has been the main resupply route for Tripoli. The rebels claimed to also capture towns to the south and east of Tripoli, tightening the noose around the capital, which is under a NATO naval blockade to the north.

If the rebels are able to hold the territory – they have made gains before, only to retreat under counterattack – it would be a major blow to Qaddafi and his forces.