Reports say armed rebel forces have gained control of the Libyan city of Zawiya, which is about 50 kilometers west of the capital, Tripoli.
Antigovernment forces shouted slogans like "Qaddafi out!" and "This is our revolution!" as unrest continued to shake the North African country.
Tripoli, meanwhile, is still in government hands.
Meanwhile, Britain today revoked diplomatic immunity for Muammar Qaddafi and his family, just a day after the United Nations unanimously approved sanctions on Libya
amid international pressure for the Libyan leader to step aside.
The UN resolution, adopted late on February 26, includes an arms embargo and slaps a travel ban and asset freeze on Qaddafi, his inner circle, and members of the Libyan leader's family.
It also calls for the International Criminal Court to probe the violence and prosecute anyone responsible for killing civilians.
British Foreign Secretary William Hague called on Qaddafi to step down in a television appearance today.
"The people of Libya have risen up against Colonel Qaddafi. We have here a country descending into civil war, with atrocious scenes of killing of protesters and a government actually making war on its own people so of course it is time for Colonel Qaddafi to go," Hague said. "That is the best hope for Libya."
U.S. President Barack Obama has also asked Qaddafi to step down, while Russia's ambassador to the UN, Vitaly Churkin, today welcomed the UN sanctions as necessary in order to keep Libya from all-out civil war.
Also today, the UN refugee agency called on the international community to help the some 100,000 people that have so far fled the violence in Libya in what the agency warned is an escalating "humanitarian crisis."
compiled from agency reports