The deputy leader of al Qaeda, Nasser al-Wuhayshi, has been killed in a U.S. bombing in Yemen, the group said on Tuesday, removing the director of a string of attacks against the West and a man once seen as a successor to leader Ayman al-Zawahri.

A close associate of Osama bin Laden in the years leading up to the Sept. 11, 2001 attacks on U.S. targets, Wuhayshi, a Yemeni in his late 30s, was named by Zawahri as al Qaeda’s effective number two in 2013.

With a $10 million price on his head offered by U.S. authorities, Wuhayshi was also leader of al Qaeda in the Arabian Peninsula, and his death potentially weakens the group, widely seen as the radical network’s strongest branch.

He led the group as it plotted foiled bomb attacks against international airliners and claimed responsibility for the deadly shooting at the French satirical newspaper Charlie Hebdo, calling it punishment for insulting the Prophet Mohammed.

Senior AQAP member Khaled Batarfi said in a video statement posted online that Wuhayshi “passed away in an American strike which targeted him along with two of his mujahideen brothers, may God rest their souls.”

The group had met and appointed its former military chief Qassim al-Raymi, also a Yemeni, as his replacement, he said.

“It’s a significant blow. He could have moved up to the top spot (in al Qaeda),” said Martin Reardon, senior vice president at the Soufan Group security consultancy.

“AQAP is widely considered the most capable terrorist group in the world,” said Reardon, a veteran of the Federal Bureau of Investigation, referring to its focus on attacks on the West.

The group has also orchestrated spectacular attacks inside Yemen in recent years, targeting government ministries, military camps and soldiers, in which hundreds of people were killed.

Al Qaeda did not specify how or when Wuhayshi was killed. Some residents of the southeastern Yemeni city of Mukalla reported a suspected drone strike on Friday.

But eyewitnesses said that last Tuesday, townspeople were gathering on the city’s seaside corniche after evening prayers when an explosion killed three men, spreading their limbs across a street as panicked residents fled.

Qaeda veteran

In an unusual move, Al Qaeda gunmen cordoned off the area and gathered the bodies, residents said, leading them to believe a radical leader was among the dead.

Wuhayshi is the sixth major AQAP leader killed in suspected U.S. bombings this year, despite political turmoil in Yemen that led to the closing of the U.S. embassy and the evacuation of its military and intelligence personnel.

Late on Monday, a U.S. official said it was examining reports of his death. A second official said the U.S. military was not involved in any strike. It was unclear whether a strike may have been carried out by the Central Intelligence Agency.

Wuhayshi, according to Gregory Johnson, author of a book on Yemen, was born in southern Yemen and traveled to Afghanistan for the first time in 1998 to join al Qaeda. He met bin Laden there and acted as his aide-de-camp until 2001, when the group was scattered after the U.S.-led invasion of Afghanistan. He became head of AQAP in 2009.

In 2013, U.S. sources said an intercepted communication between Wuhayshi and Zawahiri – believed based in Pakistan – was part of a broader pool of intelligence that led to an alert closing several U.S. embassies in the Middle East and Africa.

After an Arab military campaign against Iran-allied rebels that control much of the country’s east, AQAP has made common cause with tribal and religious groups, and residents in Mukalla say its members carry weapons and recruit there openly. Reuters