Vandals attacked the Italian and British embassies in the Libyan capital Sunday, hours after Moammar Gadhafi escaped a NATO missile strike that officials said killed one of his sons and three young grandchildren. The unrest prompted the United Nations to pull its international staff out of Tripoli.

Britain responded to the attack on its embassy complex, which left the buildings badly burned, by announcing that it was expelling the Libyan ambassador to London.

NATO's attack on a blast wall-ringed Gadhafi family compound in a residential area of Tripoli late Saturday signalled escalating pressure on the Libyan leader who has tried to crush an armed rebellion that erupted in mid-February. Libyan officials denounced the strike as an assassination attempt and a violation of international law.

The bombing also drew criticism from Russia, which cast doubt on NATO's assertion that the alliance is not targeting Gadhafi or members of his family.

"Statements by participants in the coalition that the strikes on Libya are not aimed at the physical destruction of ... Gadhafi and members of his family raise serious doubts," a Foreign Ministry statement said.

It also said the "disproportionate use of force ... is leading to detrimental consequences and the death of innocent civilians." The ministry called for "an immediate cease-fire and the beginning of a political settlement process without preconditions."

Venezuelan President Hugo Chavez, a Gadhafi ally, also condemned the strike.

NATO acknowledged that it had struck a "command and control building," but insisted all its targets are military in nature and linked to Gadhafi's systematic attacks on the population.

"It was not targeted against any individual," NATO spokeswoman Carmen Romero said Sunday, adding the report of the deaths remained unconfirmed.

British Prime Minister David Cameron, without confirming fatalities, also told the British Broadcasting Corp. that the strike was in line with the U.N. mandate to prevent "a loss of civilian life by targeting Gadhafi's war-making machine."

A NATO warplane bombed a residential complex taking up an entire block in Tripoli's Garghour neighbourhood, which is also home to several foreign embassies. The blast killed Gadhafi's second youngest son, Seif al-Arab, 29, when the Libyan leader and his wife, Safiya, were inside, said Libyan government spokesman Moussa Ibrahim. Three of Gadhafi's grandchildren, all younger than 12, were killed, but the Libyan leader was "in good health," he said. Ibrahim initially said Seif al-Arab was the youngest.

Bishop Giovanni Martinelli, the top Catholic clergyman in Tripoli, said he was shown six bodies in a hospital in the capital on Sunday. He said he was told that one of the bodies was that of Seif al-Arab Gadhafi, but that it was so badly disfigured that he could not make a positive identification.

"We saw the body. The body was completely disfigured," the bishop told The Associated Press.

He said he was told that among the bodies were those of the three children.

Footage broadcast on Libyan TV showed Martinelli and other clergymen speaking blessings in what appeared to be a morgue. Two of the bodies were covered by green Libyan flags, and a flower wreath leaned against a wall.

In addition to his eight biological children, Gadhafi also had an adopted daughter who was killed in a 1986 U.S. airstrike on his Bab al-Aziziya residential compound -- retaliation for the bombing attack on a German disco in which two U.S. servicemen were killed. The U.S. at the time blamed Libya for the disco blast.

Neighbours said the complex bombed late Saturday had served as the Gadhafi family home for years. It contained two residences, each with two bedrooms, as well as a den, a large communal space and a separate kitchen.

The kitchen clock, knocked from the wall, had stopped a 8:08 and 45 seconds, the time of the explosion. Cooking pots with leftover food, including stuffed peppers, noodles and a stew, had been covered with aluminum foil. In one of the living rooms, a pile of video games, including FIFA 10, lay scattered on a sofa.

The bombing demolished the ceiling of the main single-story building and tore a hole into the ground, displaying what looked like a basement. What appeared to be an unexploded rocket lay on the ground, which was covered by twisted metal and pieces of concrete. Hours after the blast, onlookers were permitted onto the grounds, some chanting pro-Gadhafi slogans.

In Rome, the Italian Foreign Ministry said its embassy and several others in Tripoli were damaged by vandals and accused the Gadhafi regime of failing to take measures to protect foreign missions. The ministry issued a statement Sunday following reports from Tripoli that a fire had broken out at the Italian embassy. Italy withdrew its diplomats weeks ago.

A Foreign Office spokeswoman said the British embassy buildings, which include the ambassadors' residence, have been almost completely burnt down, with only the shells remaining. She said the buildings had been "ransacked, vandalized and completely destroyed."

British Foreign Secretary William Hague said the Libyan ambassador has been given 24 hours to leave the country. "I condemn the attacks on the British Embassy premises in Tripoli as well as the diplomatic missions of other countries," he said in a statement.

The United Nations pulled its 12 international staffers out of Tripoli and sent them to neighbouring Tunisia because of unrest in the Libyan capital, said Stephanie Bunker, spokeswoman for the U.N. Office for the Coordination of Humanitarian Affairs.

U.N. international staffers remain in the rebel stronghold of Benghazi, in eastern Libya.

When news of the deadly NATO strike spread, rebels honked horns and chanted "Allahu Akbar" or "God is great" while speeding through the western city of Misrata, which Gadhafi's forces have besieged and subjected to random shelling for two months, killing hundreds. Fireworks were set off in front of the central Hikma hospital, causing a brief panic that the light would draw fire from Gadhafi's forces.

Some rebels questioned the veracity of the claim, saying the regime could be trying to discredit the international military campaign.

"We don't know if it is true or not because Gadhafi is a liar. He is probably trying to put pressure on international community. I will only believe it if you put the body in front of me," said Khaled al-Urfi, a 34-year-old metalworker.

Seif al-Arab is the second youngest of Gadhafi's seven sons and brother of the better known Seif al-Islam, who had been touted as a reformist before the uprising began. The younger Gadhafi had spent much of his time in Germany in recent years and was not involved in Libyan power structures as were many of his siblings.

Gadhafi, who has been in power for more than four decades, has fought fiercely to put down an uprising against his regime that began with protests inspired by a wave of Mideast unrest and escalated into an armed rebellion. But the two sides have been locked in a stalemate, with Gadhafi holding much of the western half of the country and the rebels maintaining their eastern stronghold.

NATO warplanes have been carrying out airstrikes in Libya for the past six weeks as part of a U.N. mandate to protect Libyan civilians.

The airstrike that killed Seif al-Arab came just hours after Gadhafi called for a mutual cease-fire and negotiations with NATO powers to end the bombing campaign. NATO rejected the offer, saying the alliance needed "to see not words but actions."

On Sunday morning, Gadhafi's troops shelled Misrata's port as a Maltese aid ship, the Mae Yemanja, unloaded food and medical supplies, said Ahmed al-Misalati, a truck driver helping move the cargo.

"We were still working this morning when they started firing rockets," said al-Misalati. "Some fell in the ocean, some on the pavement, some in the warehouses, and in the water in front of the boat."

The boat quickly embarked back to sea, he said.

Last week, regime loyalists attempted to mine Misrata's harbour to close the besieged city's only link to the world.