MISRATA, Libya - Forces loyal to Libyan leader Moammar Gaddafi launched a new armored incursion into the besieged rebel city Misrata on Monday ahead of the funeral of his son, killed in a NATO-led air strike.
Overnight fighting around Libya's third largest city killed at least six people and wounded dozens, medics said, after the deadly air raid sparked angry protests against Western diplomatic residences in Tripoli.
"Gaddafi's tanks are attempting to enter the city through Al-Ghiran," a southwestern suburb of Misrata near the airport, a rebel official said.
At least four or five tanks, which had been concealed at the government-held airport to avoid NATO air strikes, were engaged in the offensive, another rebel official said.
AFP correspondents in the Mediterranean port city heard heavy tank fire from 6:00 am (0400 GMT), answered by heavy machine-gun fire from the rebels.
"We have counted six dead and several dozen wounded," a medical official told AFP at around 9:30 am (0730 GMT) after the overnight clashes. The official had no immediate word on how many casualties were civilians.
"We have seven intensive care beds but at the moment there are eight who need them," another medic said.
"The eighth is having to make do without a respirator and the nurses are having to help him breathe manually. If we get another critically ill patient, he will die," said the doctor, a Western volunteer.
The last major rebel bastion in western Libya, Misrata is surrounded by pro-Gaddafi forces and entirely dependent on supply by sea.
Loyalist troops have repeatedly pounded the port, killing two rebel fighters on Sunday alone, witnesses said.
In the capital, preparations were under way for the funerals after afternoon prayers of Gaddafi's second youngest son Seif al-Arab, and three of his grandchildren.
Government spokesman Mussa Ibrahim told reporters early on Sunday that the house of Gaddafi's son "was attacked tonight with full power.
"The attack resulted in the martyrdom of brother Seif al-Arab Moammar Gaddafi, 29 years old, and three of the leader's grandchildren," Ibrahim added.
Gaddafi and his wife were in the building with his son, Ibrahim said, calling the strike "a direct operation to assassinate the leader," who he said "is in good health -- he wasn't harmed. His wife is also in good health."
Ibrahim said Gaddafi's location was "leaked."
"They knew about him being there, or expected him for some reason."
The children killed were a boy and a girl, both aged two, and a baby girl of four months, he said.
Demonstrators torched vacant British and Italian diplomatic buildings in Tripoli in response, prompting Britain to expel the Libyan ambassador.
"The Vienna Convention requires the Gaddafi regime to protect diplomatic missions in Tripoli," British Foreign Secretary William Hague said.
"By failing to do so that regime has once again breached its international responsibilities and obligations."
The Italian foreign minister denounced the "grave and vile actions."
Britain had recalled its envoy to Tripoli at the start of the conflict, and Italy closed its mission in March.
Libya's Deputy Foreign Minister Khaled Kaim called the attacks on diplomatic missions "regrettable," and said Tripoli would take responsibility for repairs.
He said police had been overwhelmed by the crowds.
The Roman Catholic Bishop of Tripoli, Giovanni Martinelli, confirmed to an Italian television channel that Seif al-Arab had been killed.
He appealed for an end to the bombing. "I ask, please, out of respect for the pain due to the loss of a son, a gesture of humanity towards the leader," he said.
Dr Gerard Le Clouerec, a French surgeon working at a private clinic in Libya, said he examined the body of a man who was, in comparison to photos, "most probably the son of Colonel Gaddafi," along with the bodies of two young children whose faces had "disappeared."
In his estimation, all three were killed in an explosion.
On a guided visit on Sunday, Ibrahim showed journalists a heavily damaged house in the Gharghour area where the attack took place.
The Western alliance vowed more strikes, although the operation commander stated "we do not target individuals."
"All NATO's targets are military in nature and have been clearly linked to the... regime's systematic attacks on the Libyan population and populated areas," said Lieutenant General Charles Bouchard.
He said raids would continue until threats against civilians ceased and all of Gaddafi's forces "have verifiably withdrawn to their bases, and until there is full, free and unhindered access to humanitarian aid to all those in Libya who need it."
An international coalition began carrying out strikes on March 19, under a UN Security Council mandate to protect civilians. NATO took command of operations on March 31.