NATO forces flattened a building inside Muammar Gaddafi's Bab al-Aziziyah compound early on Monday, in what a press official from Gaddafi's government said was an attempt on the Libyan leader's life.
Foreign journalists were brought to the scene in Tripoli when firefighters were still working to extinguish flames in a part of the ruined building a few hours after the attack.
The press official, who asked not to be identified, said 45 people were hurt in the strike, 15 of them seriously, and some were still missing. That could not be independently confirmed.
Gaddafi's compound has been struck before, but NATO forces appear to be stepping up the pace of strikes in Tripoli in recent days.
In Brussels, a NATO spokesman, said the alliance is increasingly targeting facilities linked to Gaddafi's regime with government advances stalled on the battlefield.
"We have moved on to those command and control facilities that are used to coordinate such attacks by regime forces," the spokesman said, on condition of anonymity, of the strike on Bab al-Azizya.
A target nearby, which the government called a car park but which appeared to cover a bunker, was hit two days ago.
The United States, Britain and France say they will not stop their air campaign over Libya until Gaddafi leaves power.
Meanwhile, Saif al-Islam Gaddafi, the Libyan leader's son, struck a tone of defiance. He claimed that Gaddafi has "millions of Libyans with him" and said NATO's mission was doomed to fail.
"The bombing which targeted Muammar Gaddafi's office today...will only scare children. It's impossible that it will make us afraid or give up or raise the white flag," he was quoted as saying by the Jana state news agency.
"You, NATO, are waging a losing battle because you are backed by traitors and spies. History has proved that no state can rely on them to win."
Washington has taken a backseat in the air war since turning over command to NATO at the end of March but is under pressure to do more. This week it deployed Predator drone aircraft, which fired for the first time on Saturday.
Government troops bombarded the western rebel bastion of Misurata again on Sunday, a day after announcing their withdrawal following a two-month siege.
A government spokesman said the army was still carrying out its plan to withdraw from the city, but had fired back when retreating troops were attacked.
"As our army was withdrawing from Misurata it came under attack by the rebels. The army fought back but continued its withdrawal from the city," Mussa Ibrahim told reporters.
The government says its army is withdrawing from the city and sending in armed tribesmen instead. Rebels say the announcement may be part of a ruse to mask troop movements or stir violence between rebels and locals in nearby towns.
Rebel leader Mustafa Abdel Jalil told a news conference in Kuwait that the Gulf state had agreed to contribute $177m to his rebel council to help pay workers in the east of the country under its control.
"This amount will help us a lot in paying the salaries of employees who did not [get paid] for two months," he said.
"We are capable of only covering 40 per cent of this amount. We are in need of urgent aid."
The rebels have been seeking international recognition as well as material support from the West and the Arab world.
They have been unable to advance from eastern Libya as they fight back and forth with Gaddafi's troops on the coastal road between the towns of Ajdabiya and Brega, hampered by their lack of firepower, equipment and training.