MojNews_ "I authorized a precision strike that would remove him from the battlefield, once and for all," Biden said.

Zawahiri, who just turned 71 years old, had remained a visible international symbol of the group, 11 years after the US killed Osama bin Laden. At one point, he acted as bin Laden's personal physician.

Zawahiri was sheltering in downtown Kabul to reunite with his family, Biden said, and was killed in what a senior administration official described as "a precise tailored airstrike" using two Hellfire missiles. 

The drone strike was conducted at 9:48 p.m. ET on Saturday was authorized by Biden following weeks of meetings with his Cabinet and key advisers, the official said on Monday, adding that no American personnel were on the ground in Kabul at the time of the strike.

Senior Haqqani Taliban figures were aware of Zawahiri's presence in the area, the official said, in "clear violation of the Doha agreement," and even took steps to conceal his presence after Saturday's successful strike, restricting access to the safe house and rapidly relocating members of his family, including his daughter and her children, who were intentionally not targeted during the strike and remained unharmed. The US did not alert Taliban officials ahead of Saturday's strike.

In a series of tweets, Taliban spokesman Zabiullah Mujahid said, "An air strike was carried out on a residential house in Sherpur area of Kabul city on July 31."

He said, "The nature of the incident was not apparent at first" but the security and intelligence services of the Islamic Emirate investigated the incident and "initial findings determined that the strike was carried out by an American drone."

The tweets by Mujahid came out prior to CNN reporting Zawahiri's death. Mujahid said the Islamic Emirate of Afghanistan "strongly condemns this attack on any pretext and calls it a clear violation of international principles and the Doha Agreement."