The rebels are also struggling to defend Misrata, Libya's third city, under an onslaught from regime forces. The city which lies about 215 kilometres east of Tripoli has seen fighting for more than 40 days since the start of the uprising against Kadhafi. Doctors say 200 people have been killed there since the fighting began.
On Thurday, a World Food Programme ship carrying food, medicines and doctors arrived at Misrata with 600 tonnes of foodstuffs which is estimated to be enough to feed more that 40,000 people for a month.
Meanwhile, a top US general claims it is unlikely that Libyan forces could oust Kadhafi and the conflict appears to be turning into a stalemate.
General Carter Ham, who led the first stage of the coalition air campaign in Libya, said the raid had succeeded in protecting civilians for the most part, but the regime would not be removed by military means.
His comments underscored growing concern in Washington and European capitals that the fight in Libya could be deadlocked.