A wave of Nato air strikes battered Tripoli on early Wednesday, piling pressure on embattled Libyan leader Muammar Gaddafi who said he was "near" the bombing but vowed never to surrender.
Loud blasts were heard near Gaddafi's residential complex Bab al-Aziziya at around 1.45am (2345 GMT Tuesday), an AFP correspondent said. A little later the city was shaken by more powerful explosions.
On Tuesday, in one of the heaviest bombardments of the air war so far Nato-led warplanes carried out some 60 strikes on Tripoli, killing 31 people, Libyan government spokesman Mussa Ibrahim said.
The main target was Gaddafi's compound which has been blasted regularly since the start of the international military intervention on March 19, and most of the buildings in the Bab al-Aziziya complex have been flattened.
In an audio message broadcast late Tuesday, Gaddafi said that he was close to the bombing but was still resisting and called on his people to resist too.
"Despite the bombings, we will never submit," Gaddafi said in the nine-minute broadcast. "I am near the bombing but I am still resisting.
"We have only one choice - (to stay in) our country to the end. Death, life, victory, no matter what. We will not leave our country or sell it, we will not submit," he said in his first intervention since he appeared on state television on May 19.
Shortly after the recording was broadcast, more air strikes hit the Libyan capital, continuing a bombardment that had gone on throughout the day.
Journalists taken on an escorted tour of the bomb-damaged compound were shown a dead body, draped in a green Libyan flag, which government spokesman Mussa Ibrahim said was one of a number of casualties from the air strikes.
An information ministry minder said that six bombs had struck the compound itself and eight the barracks just opposite.
The British defence ministry said targets included a secret police headquarters in the heart of Tripoli and a major military installation on the outskirts.
In Brussels, where Nato defence ministers were to meet on Wednesday to discuss the progress of the Libya campaign, Gaddafi's daughter Aisha filed a war crimes complaint against the Western alliance, claiming it knowingly bombed a civilian target, killing her daughter and other family members.
The complaint, a copy of which was seen by AFP, relates to an April 30 Nato raid on Tripoli, which Libyan officials said killed the strongman's youngest son and three grandchildren.
In Washington, US President Barack Obama said after talks with German Chancellor Angela Merkel that the pressure on Gaddafi "will only continue to increase" until the Libyan leader steps down.
"The chancellor and I have been clear. Gaddafi must step down and hand power to the Libyan people, and the pressure will only continue to increase until he does," Obama told reporters at the White House, standing alongside the German leader.
"What you're seeing across the country is a inexorable trend of the regime forces being pushed back, being incapacitated.
"You're seeing defections, often times of some very high-profile members of the Gaddafi government, as well as the military.
"I think it is just a matter of time before Gaddafi goes."
Labour minister Al-Amin Manfur became the latest member of Gaddafi's regime to defect, announcing at a meeting of the International Labour Organisation in Geneva that he was changing sides.
In Libya's second city Benghazi, President Dmitry Medvedev's envoy Mikhail Margelov met rebel leaders in the first trip by a top Russian official to their eastern stronghold.
Margelov, Medvedev's African envoy, said Russia was prepared to provide financial support to the rebels but opposed any escalation of the conflict.
The rebels said they were ready to receive Russian aid "tomorrow," but stressed that they would not enter any negotiations until Gaddafi stepped down.
Margelov said Moscow was prepared to "facilitate dialogue between the two camps," but Foreign Minister Sergei Lavrov stressed Russia did not want to be the lead mediator.
"We have said several times that the African Union has the main role," Lavrov told reporters on a visit to Nato member Norway.
In Washington, a senior US official said the United States is prepared to welcome a Libyan woman who accused Gaddafi's soldiers of raping her as long as she goes through the normal refugee process.
The woman, Iman al-Obeidi, is currently at the emergency transit center in Timisoara, Romania, along with about 100 other evacuees from different locations, according to UN refugee officials.
Al-Obeidi, 29, attracted international media attention when she stormed into the Rixos hotel in Tripoli on March 26 and threw open her coat to reveal scars and bruises on her body.
She accused forces loyal to Gaddafi of abusing her after she was stopped at a checkpoint in Tripoli.