The official said the Libyan-born Libi, a cleric whose real name was Mohamed Hassan Qaid, was killed in a drone strike early morning Monday, Pakistan time. The drone-launched missile was targeted at a suspected militant hideout in Hesokhel, a village in North Waziristan, a tribal region in Pakistan along its border with Afghanistan.

U.S. officials said that Libi, who had appeared in al Qaeda propaganda videos and once escaped from an a U.S.-operated prison in Afghanistan, was a key figure in what remained of the core al Qaeda network founded by Osama bin Laden, who was killed last year in a U.S. commando raid on his hideout near a Pakistani military academy.

The officials spoke on condition of anonymity to discuss intelligence matters.

In the wake of bin Laden’s death, officials said, Ayman al Zawahri, an Egyptian doctor who had been bin Laden’s long-time deputy, became the leader of al Qaeda’s core group, advised and assisted by a small coterie of veteran militants. U.S. officials said Libi had recently emerged as Zawahri’s principal deputy.

“Abu Yahya was among al Qaeda’s most experienced and versatile leaders – operational trainer and Central Shura head – and played a critical role in the group’s planning against the West, providing oversight of the external operations efforts,” one official said.

Zawahri “will be hard-pressed to find any one person who can readily step into Abu Yahya’s shoes – in addition to his gravitas as a longstanding member of AQ’s leadership, Abu Yahya’s religious credentials gave him the authority to issue fatwas, operational approvals, and guidance to the core group in Pakistan and regional affiliates,” the official added. “There is no one who even comes close in terms of replacing the expertise AQ has just lost.”

U.S. officials waited more than 24 hours before spreading word that they were confident Libi had been killed. In addition to his escape, along with three other militants, from U.S. custody in 2005, he at least once had been reported, prematurely, to have been killed in a U.S. drone strike.

The officials declined to say why they were so confident that Libi was now dead. DM

Photo: Undated handout image courtesy of the US Air Force shows a MQ-1 Predator unmanned aircraft. REUTERS/US Air Force