Libya's government says more civilians have been killed in a third night of air and missile strikes by coalition forces enforcing a no-fly zone.
Explosions and anti-aircraft fire have been heard near Col Muammar Gaddafi's compound in the capital, Tripoli.
Fighting between the forces loyal to the Libyan leader and the rebels has also continued, despite the declaration of a ceasefire by the government.
In the east, troops beat back a rebel advance outside the town of Ajdabiya.
And rebels in Libya's third city, Misrata, told the BBC that they had come under attack from Col Gaddafi's forces during the day.
Meanwhile, President Barack Obama said the US would transfer its leading role on Libya "within days" to ensure the burden of enforcing the no-fly zone was shared.
He also said the US wanted to see Col Gaddafi removed from power but insisted the current campaign was focused on protecting civilians.
'Under siege'
The BBC's Allan Little in Tripoli says the sky above the capital lit up with anti-aircraft fire again on Monday night.
Our correspondent heard one loud explosion nearby and several distant rumbles much further afield. The AFP news agency reported that a blast was heard near Col Gaddafi's Bab al-Aziziya compound.
Libyan state television reported that the capital was "under crusader enemy aerial bombardment" and that several sites had been attacked.
"These attacks are not going to scare the Libyan people," it said.
Libyan government spokesman Moussa Ibrahim told a news conference that the southern town of Sebha had been attacked on Monday. He said the coalition also attacked a "little fishing port" near Tripoli.
A witness told the AFP news agency that a Libyan naval base at Bussetta, about 10km (six miles) east of Tripoli, had been bombarded. The al-Jazeera TV channel also reported that radar stations at two air bases east of Benghazi had been hit.
Mr Ibrahim said Monday's air and missile strikes had caused "numerous" civilian casualties, especially at the "civilian airport" in Sirte.
A doctor in Misrata - the last rebel-held city in western Libya - told the BBC that residents had suffered another night of shelling by government forces. "Our clinic is full of patients," he said.
The town of Zintan, near the Tunisian border, was also shelled by Col Gaddafi's forces on Monday, destroying houses and a mosque, witnesses told the Reuters news agency. One said there were 40 tanks on the outskirts.
The reports could not be independently verified.
In the east, troops loyal to the Libyan leader opened fire with tanks, beating back an advance by opposition fighters outside Ajdabiya.
Diminishing US role
Rebel leaders based in eastern Libya have had talks with United Nations officials on the humanitarian situation there.
The BBC's Kevin Connolly in Tobruk, where the talks were held, says that although food is being imported in the region from Egypt, it is not clear how viable the local economy will be if it remains cut off from the rest of Libya.
President Obama has said that while "it is US policy that Gaddafi has to go", the operation in Libya was about protecting civilians.
"Our military action is in support of an international mandate from the Security Council that specifically focuses on the humanitarian threat posed by Col Gaddafi to his people. Not only was he carrying out murders of civilians but he threatened more," he told reporters during a visit to Chile.
The US, UK and France have insisted that the Libyan leader is not a target. On Sunday, a three-storey building in the Bab al-Aziziya compound was destroyed by a missile.
Mr Obama also said the US would soon cede control of the operation - "in a matter of days and not in a matter of weeks" - but divisions have emerged over a possible transfer of command to Nato.
US Defence Secretary Robert Gates has said the mission could be under French-British or Nato control. But some allies - including France and Turkey - are opposed to Nato taking over.
Norway said its jets would not take part in the action as long as it was unclear who was in overall command.
