Blasts and anti-aircraft fire rattled the Libyan capital Thursday as allied air raids against Muammar Gaddafi 's forces entered a sixth day and a British officer said Libya's air force was mostly obliterated.
The raids appear set to continue for the forseeable future with France hailing the success of the operation while British Air Vice Marshal Greg Bagwell claimed Libya's air force had been almost totally obliterated and "no longer exists as a fighting force."
French Foreign Minister Alain Juppe told RTL radio the strikes were a "success" and would "continue as long as necessary" and denied reports that the airstrikes had killed civilians, saying "it is the exact opposite."
Juppe also indicated that France, which has so far blocked calls from the United States and much of the West to place responsibility for the campaign in the hands of NATO, was now in favour of handing over responsibility for implementing a UN-approved "no-fly" zone to the alliance.
France has insisted on a committee of coalition countries so as not to alienate Arab states, while Italy has demanded a single command under NATO.
After talks broke down, a NATO diplomat said the 28-nation alliance would try again on Thursday to reach a decision.
A British submarine launched a fresh salvo of Tomahawk missiles at Libyan air defence systems, Major General John Lorimer, the spokesman for the chief of defence staff, said, but gave no details about the targets or the result of the strikes.
US officials are also openly speculating whether the continued pressure will force Gaddafi out of power after four decades in control.
Witnesses reported a huge blast Wednesday night at a military base in the Tajura residential neighbourhood some 32 kilometres (20 miles) east of the capital, while anti-aircraft fire was heard as warplanes thundered over Tripoli.
The official JANA news agency said coalition raids on Tajura killed "a large number" of civilians.
Tajura was struck three times, the agency said, adding the third raid "targeted rescuers who were trying to remove the dead and wounded from the rubble and the destruction caused by the first two raids."
The claims could not be independently confirmed.
Tajura is home to the most important Libyan military bases and was struck by allied forces on the first day of operations on Saturday, launched against Libya to impose a UN no-fly zone on the country.
Although the endgame in Libya remains unclear, US Defence Secretary Robert Gates said during a visit to Egypt that mounting pressure on Gaddafi 's regime could encourage his associates or even members of his family to turn on him.
"I think there are any number of possible outcomes here and no one is in a position to predict them, whether there are further major defections within his own ruling circle, whether there are divisions within his family," he said.
US President Barack Obama has insisted Gaddafi must step down, and US officials hinted that members of Gaddafi’s inner circle were reaching out to find a way out of the crisis.
The US military also said Gaddafi’s ground troops threatening rebel-held cities were now being targeted by coalition air strikes.
"We are putting pressure on Gaddafi 's ground forces that are threatening cities," said Rear Admiral Gerard Hueber, US chief of staff for the Libya mission.
French Defence Minister Gerard Longuet said, "The air exclusion zone has become a reality."
"The French side has taken out a dozen armoured vehicles in three days," he told Le Figaro newspaper in an interview published on Thursday. "This is decisive as we have practically not seen any tank concentrations since the strikes."
Canadian warplanes bombed their first target in Libya overnight, destroying a munitions depot in the rebel-held city of Misrata, Libya's third city 214 kilometres (132 miles) east of Tripoli, military officials said.
White House spokesperson Ben Rhodes confirmed that after forcing Gaddafi’s forces to pull back from eastern Benghazi "we're similarly focused on trying to protect the people of Misrata as well."
Late on Wednesday, Gaddafi forces using tanks pounded the only hospital in Misrata, which has been besieged by regime loyalists for weeks, a witness and a rebel spokesperson said.
"The situation here is very bad and very serious. The tanks are shelling the hospital and houses," said the spokesman. On Tuesday 17 people were killed by snipers and shelling in Misrata, a doctor said.
Residents on Wednesday fleeing Ajdabiya, a strategic eastern town south of rebel capital Benghazi, described shelling, gunfire and burning houses, while an AFP reporter said a pall of smoke hung over the town and intermittent explosions were heard.
UN chief Ban Ki-moon again urged all sides in Libya to cease fire as the Security Council prepared to meet on Thursday, a week after clearing the way for action against Gaddafi .
"All those who violate international humanitarian and human rights law will be held fully accountable," Ban's spokesman Martin Nesirky said, mentioning attacks on Misrata and Zintan, also in the west.
Coalition forces are acting under UN Security Council Resolution 1973 authorising "all necessary means" to protect civilians fighting to topple Gaddafi , including enforcing a no-fly zone.
Six nations agreed to contribute up to 16 vessels to prevent Gaddafi from bringing in weapons via the Mediterranean, with Turkey offering five warships and a submarine despite its reservations about the military action.
Meanwhile, US Secretary of State Hillary Clinton said Washington expects "more announcements" of Arab participation in the campaign in the coming days.
Qatar has deployed Mirage fighters, the only Arab state so far to commit military assets to the coalition. British Prime Minister David Cameron said Kuwait and Jordan would provide a logistical contribution.