Forces loyal to Libyan leader Colonel Muammar Gaddafi have made major gains against anti-government rebels, pushing them from two key areas.
The BBC reports Western journalists in the city of Zawiya, west of Tripoli, confirmed the Gaddafi regime's claims that the city had fallen after days of bombardment.
Rebels have also fled from the oil port of Ras Lanuf in the east.
There have been reports of severe civilian casualties after rebel positions and residential areas came under fire from rockets and shells.
A witness says he saw dozens of bodies in the residential part of the town, the BBC reports.
Government planes also targeted Brega, another oil port further east.
And Colonel Gaddafi's son Saif al-Islam warned the rebel stronghold of Benghazi that government troops were on their way.
Rebel leader appeals to world
Mustafa Abdul Jalil, who has emerged as the main opposition leader, speaking to the BBC, urged the international community to follow the lead of France by recognising the rebel administration in Benghazi as the legitimate government of Libya.
He called on Western governments to help with the fight, saying: "Everybody should know that there is no balance between our capabilities and Muammar Gaddafi's."
Meanwhile, the United States Director of National Intelligence, James Clapper, has told a Senate hearing he expects Colonel Gaddafi to win his battle to stay in power because his forces have better equipment and training.
