Libyan leader Muammar Gaddafi taunted Nato, saying he was alive despite a series of air strikes and "in a place where you can't get to and kill me".

The defiant audio recording was broadcast last night after the Libyan government accused Nato of killing 11 Muslim clerics with a strike on a disputed eastern oil town.

Gaddafi had appeared on state TV but had not been heard speaking since a Nato attack on his Tripoli compound two weeks ago, which officials said killed one of his sons and three grandchildren.

In a brief recording played yesterday on Libyan TV, Gaddafi said he wanted to assure Libyans concerned about a strike this week on his compound in Tripoli.

"I tell the coward crusaders - I live in a place where you can't get to and kill me," he said. "I live in the hearts of millions."

He referred to a Nato air strike on Thursday that targeted his Bab al-Aziziya compound in Tripoli, claiming it had killed "three innocent journalist-civilians".

Hours after Gaddafi's minute-long speech, the sound of four explosions - most likely a Nato strike - could be heard in Tripoli.

Also in the Libyan capital, an activist said today he witnessed 50-60 residents attacking military trucks in the western neighbourhood of Abu Sitta.

He said the events took place late last night. The doctor-turned-activist said the residents burned a military truck.

"Everybody escaped after some cheering," he said.

Government spokesman Ibrahim Uthman said the strikes targeted the country's agriculture ministry. The same building, however, was targeted days ago and, at the time, residents said it was a government intelligence building.

Reporters could not immediately verify the information. They may only to leave their hotel in the company of government officials.

On Thursday reporters were shown the air strike damage by Libyan officials, including one who said Gaddafi and his family had moved away from the compound some time ago.

One missile appeared to have targeted some sort of underground bunker at the compound - a sprawling complex of buildings surrounded by towering concrete blast walls

Many people "driven by their love for me put in many calls to check on my wellbeing after they heard of the cowardly missile attack of the crusaders on Bab al-Aziziya last Thursday, May 12," Gaddafi said in the recording, which lasted just over a minute.

Nato shrugged off the statement.

"We are not targeting him, our targets are solely military," alliance spokeswoman Carmen Romero said in Brussels.

Shortly before Gaddafi's remarks were broadcast, regime spokesman Moussa Ibrahim claimed Nato had attacked Brega while dozens of imams and officials from around Libya were gathered there to pray for peace.

Ibrahim said 11 imams were killed in their sleep at a guesthouse, and 50 people were wounded, including five in a critical condition.

One of the murdered men was wearing beige military clothing.

The alliance, responding to the claim, said it had attacked a military command-and-control centre in Brega, 450 miles south east of Tripoli.

"We're very careful in the selection of our targets and this one was very clearly identified as a command centre," said an official at Nato's operational headquarters in Naples, Italy.

Nato has been intensifying strikes in several areas of Libya against Gaddafi's troops in a bid to weaken his campaign against a rebel uprising.

Ibrahim dismissed comments from Italy's foreign minister, Franco Frattini, suggesting that Gaddafi may have been wounded and had possibly fled Tripoli.

"The leader is in very good health, high morale and high spirits," Ibrahim said. "He is in Tripoli, he is fighting... He is leading the country day by day."