NATO late Thursday agreed to take control of enforcing a no-fly zone in Libya to thwart the forces of Libyan leader Moamer Kadhafi, as coalition air strikes targeted Tripoli for the sixth straight day.
NATO Secretary General Anders Fogh Rasmussen said that after days of fraught talks, as NATO member Turkey objected to air strikes against Kadhafi's forces, the 28-member alliance had finally reached a deal.
"We have now decided to enforce the no-fly zone over Libya," he said in a statement, adding "we are taking action as part of a broad international effort to protect civilians against the Kadhafi regime."
Rasmussen later told CNN that the alliance was considering whether to expand the NATO operation to include a broader role to use all necessary means to protect civilians on the ground. Coalition air strikes in recent days have also targeted Libyan ground forces.
The news came as anti-aircraft fire raked the Tripoli skies late Thursday, with at least three explosions shaking the capital and its eastern suburb of Tajura, AFP journalists said.
At least one blast was heard from the centre of the city, while others came from Tajura -- home to military bases -- and a column of smoke rose from an undetermined location, an AFP journalist said.
State television reported that "civilian and military sites in Tripoli and Tajura" had come under fire from "long-range missiles."
Fighting also raged in rebel-held Misrata, where a medic said dozens had been killed and hundreds wounded in a week of assaults.
"Attacks by Kadhafi forces since last Friday have killed 109 people and wounded 1,300 others, 81 of whom are in serious condition," said the doctor working in the state hospital some 214 kilometres (132 miles) east of Tripoli.
Relentless British, French and US air strikes since Saturday have been targeting Kadhafi's air defenses in a bid to protect civilians under the terms of a UN resolution adopted last week.
The strikes are also providing cover for a rag-tag band of rebels seeking to oust Kadhafi after more than four decades in power, but who are heavily out-gunned by pro-regime forces and disorganized.
A bid by a Kadhafi fighter plane to flout the no-fly zone was swiftly punished Thursday when a French fighter destroyed the warplane just after it landed in the city of Misrata east of Tripoli, the French military said.
The Rafale jet, one of about 20 French planes flying over Libyan airspace, fired an air-to-surface AASM missile at the Libyan aircraft, which had been detected by a US AWACS surveillance plane.
Washington, meanwhile, urged the Libyan military to stop obeying Kadhafi's orders and said more than 350 aircraft were taking part in coalition operations.
"Our message is simple: stop fighting, stop killing your own people, stop obeying the orders of Colonel Kadhafi," Vice Admiral William Gortney said.
"It's fair to say the coalition is growing in both size and capability every day," he said, adding "more than 350 aircraft are involved in some capacity. Only slightly more than half belong to the United States."
The Pentagon said 12 countries were now taking part in the coalition seeking to enforce the no-fly zone -- including two Arab nations, Qatar and the United Arab Emirates. A senior US official said the UAE had contributed 12 aircraft.
Anti-aircraft fire and explosions also rattled the coastal city of Sirte, Kadhafi's home town 600 kilometres (370 miles) east of Tripoli, a resident said.
Kadhafi forces continued to lay siege Thursday to the cities of Misrata and Zentan, both east of Tripoli. And rebels fought to retake the oil city of Ajdabiya which sits at a junction on roads leading from rebel strongholds Benghazi and Tobruk in eastern Libya.
Rebels were in striking distance of Ajdabiya, an AFP journalist said, with shelling and gunfire heard nine kilometres (five miles) from the city where hundreds of fighters massed in the morning before marching forward.
"They are shooting at us with tanks, artillery and Grad missiles," said Mohammed, a rebel returning from the frontline. "We have nothing but light weapons whereas they have heavy ones."
Later rebel army spokesman Ahmed Omar Bani told his first news conference that insurgents were negotiating the surrender of Kadhafi loyalists in Ajdabiya.
"Some of the Ajdabiya militias have asked to surrender," said the air force general in Benghazi. "We are trying to negotiate with these people in Ajdabiya because we are almost sure that they have lost contact with the headquarters."
There were also reports from the southern stronghold of Sebha that the coalition had carried out intensive air raids on the town, bastion of Kadhafi's Guededfa tribe and site of an important military base.
A government spokesman in Tripoli said almost 100 civilians had been killed since the coalition air strikes began on Saturday, giving a provisional toll which could not be independently confirmed.
The US general in charge of the operation said coalition forces imposing the no-fly zone "cannot be sure" there have been no civilian deaths from bombings but are trying to be "very precise."
General Carter Ham, head of US Africa Command, also said Libya's air defence sites "essentially no longer exist" after being taken out by the strikes and that coalition forces were now targeting Libyan troops attacking civilians.
UN chief Ban Ki-moon meanwhile told the Security Council that Kadhafi's troops were ignoring the UN ceasefire order and that human rights abuses continued in the north African country.
"Libyan authorities have repeatedly claimed they have instituted a ceasefire," Ban said at UN headquarters in New York. "We see no evidence that that is the case. On the contrary, fierce battles have continued."
Russian President Dmitry Medvedev telephoned US President Barack Obama, urging him to avoid civilian casualties in Libya and limit the international campaign to the goals set by the United Nations.
Russia abstained from last week's vote authorising the no-fly zone.
But Foreign Minister Alain Juppe of France, which had pushed hard to secure the UN resolution, said coalition air strikes would "continue for as long as necessary."