Forces loyal to Libyan leader Muammar Gaddafi have launched a new armoured incursion into the besieged rebel city Misrata as his son, killed in a NATO-led air strike, was buried in Tripoli.
AFP correspondents heard heavy shelling throughout the morning as loyalist tanks thrust into the western suburbs of Libya's third largest city.
At least four people were killed and some 30 wounded in the fighting, medical sources said. Clashes overnight had killed another six and wounded dozens more.
"The tanks are in Al-Ghiran and Zawiyat Al-Mahjub and have been halted by our men," a rebel commander told AFP.
AFP correspondents reported one or more NATO aircraft over the city for more than two hours, but no air strikes were heard.
Residents expressed exasperation at the lack of a military response from the Western alliance to Gaddafi's armour.
"NATO has to help us. What are they waiting for?" asked one.
'Fear is mounting in Misrata'
Unlike on previous days of the more than six-week-long siege of Misrata, the resident declined to give his name - an indication of the mounting fear in the city that Gaddafi's forces are poised to retake it.
The last major rebel bastion in western Libya, Misrata is surrounded by pro-Gaddafi forces and entirely dependent on supply by sea.
NATO forces were searching for a rogue anti-ship mine laid by Gaddafi forces near Misrata last week, the alliance said on Monday.
Four small boats were caught dropping three mines off the port on Friday, but only two were found and disarmed, a NATO statement in Brussels said.
"Two were moored to the seabed and were later destroyed, but a third mine drifted free before specialised ships could arrive," it said.
Late on Monday, Misrata was again targeted by rockets and shells, an AFP reporter said, and heavy explosions were heard in the port area.
Gaddafi's son and grandchildren killed in NATO airstrike
In the capital, more than 1,000 people attended the funerals of Gaddafi's second youngest son.
Regime spokesman Moussa Ibrahim told reporters early on Sunday that Saif al-Arab was killed in the air strike on a Tripoli compound, along with three of the leader's grandchildren.
They were a boy and a girl, both aged two, and a baby girl of four months.
The official JANA news agency said funerals were held on Monday for "Saif al-Arab Muammar Gaddafi and three grandchildren of the brother-leader of the revolution."
No small coffins had been immediately visible at the procession in Al-Hani cemetery, where some mourners fired guns in the air and chanted pro-Gaddafi slogans, an AFP correspondent said.
"Revenge for martyrs! People want Muammar, the guide!" chanted the crowd as the body of Saif al-Arab, covered in a green cloth with a wreath on top, was carried for burial.
Crowds also chanted slogans against French President Nicolas Sarkozy.
The funeral was attended by Catholic Bishop Giovanni Martinelli, who has been critical of international coalition air strikes on pro-Gaddafi forces.
Ibrahim had said on Sunday that Gaddafi and his wife had been in the building when his son's house was attacked, and called the strike "a direct operation to assassinate the leader."
But neither Gaddafi nor his wife was harmed, he said.
Diplomatic buildings torched
Demonstrators torched vacant British and Italian diplomatic buildings in Tripoli in response to the raid, prompting Britain to expel Libya's ambassador.
A Transitional National Council statement in rebel stronghold Benghazi slammed the burnings, saying: "This is a clear sign that Gaddafi does not respect international law."
Rebels welcome Bin Laden death
The rebels also welcomed the death of al-Qaeda chief Osama Bin Laden and said it would be "a great gift" if the United States now killed Gaddafi.
Italy boosted security checks on Sunday after Gaddafi threatened to "bring the battle to Italy" following Rome's decision to join the NATO-led air strikes.
But on Monday Prime Minister Silvio Berlusconi sought to play down the threats, attributing them to Gaddafi's "disappointment" in Italy, Libya's former colonial ruler.
Turkey closed its embassy late on Sunday following the attacks on the British and Italian diplomatic missions, Foreign Minister Ahmet Davutoglu said.
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."
China renewed its call for a ceasefire and urged NATO not to exceed the terms of the UN Security Council resolution which provided for military action to protect civilians.
An international coalition began carrying out strikes on March 19 under the UN Security Council mandate. NATO took command of operations on March 31.
