A defiant Moammar Gadhafi threatened Friday to carry out attacks in Europe against "homes, offices, families," unless NATO halts its campaign of airstrikes against his regime in Libya.

The Libyan leader, sought by the International Criminal Court for brutally crushing an uprising against him, delivered the warning in an audio message played to thousands of supporters gathered in the main square of the capital Tripoli.

Several hours later, a series of powerful explosions rattled the heart of the capital, apparently new NATO airstrikes, as Gadhafi supporters cheered, honked horns and fired into the air in the street. Black smoke could be seen rising from the area near Gadhafi's Bab al-Aziziya compound.

Gadhafi spoke from an unknown location in a likely sign of concern over his safety. Addressing the West, Gadhafi warned that Libyans might take revenge for NATO bombings.

"These people [the Libyans] are able to one day take this battle ... to Europe, to target your homes, offices, families, which would become legitimate military targets, like you have targeted our homes," he said.

"We can decide to treat you in a similar way," he said of the Europeans. "If we decide to, we are able to move to Europe like locusts, like bees. We advise you to retreat before you are dealt a disaster."

Friday's was one of the largest pro-government rallies in recent weeks.

It came just four days after the International Criminal Court issued arrest warrants for Gadhafi, his son Seif al-Islam and Libyan intelligence chief Abdullah al-Sanoussi for crimes against humanity. International prosecutors allege government troops fired on civilian protesters during anti-Gadhafi street demonstrations earlier this year.

It looked unlikely those warrants would be executed anytime soon, however, as the African Union decided Friday at its summit in Equatorial Guinea that its member countries would not arrest Gadhafi.

The popular uprising against the Libyan ruler has turned into a protracted civil war, with anti-government rebels controlling much of eastern Libya and parts of Libya's western mountains. NATO has been bombing government-linked targets since March in the wake of UN Security Council Resolution 1973, which authorized "all necessary measures," short of a ground invasion, to protect civilians.

Calls rebels traitors

In his speech Friday, Gadhafi denounced the rebels as traitors and blamed them for Libya's troubles. He said Libyans who fled to neighbouring Tunisia are now "working as maids for the Tunisians."

"What brought you to this stage? The traitors," Gadhafi said in the audio message.

He urged his supporters to "march on the western mountains" to clear the area of weapons the French government delivered to the rebels there several days ago.

It was not immediately clear whether the Libyan leader could make good on his threats against Europe. In the past, Gadhafi supported various militant groups, including the IRA and several Palestinian factions, while Libyan agents were blamed for attacks in Europe, including a Berlin disco bombing in 1986 and the downing of Pan Am Flight 103 over Lockerbie, Scotland, that killed 270 people, mostly Americans. Libya later acknowledged responsibility for Lockerbie.

In recent years, however, Gadhafi was believed to have severed his ties with extremist groups when he moved to reconcile with Europe and the United States.

Al-Qaeda and other jihadi groups have opposed Gadhafi since he cracked down in the late 1990s on the Islamist Libyan Islamic Fighting Group, which sought to replace his regime with an Islamic state.