U.S. kills top al-Qaida leader and key 9/11 plotter, Ayman al-Zawahiri : NPR

Top al-Qaida leader and key 9/11 plotter Ayman al-Zawahiri was killed by a drone strike carried out by the U.S. on July 30, according to President Joe Biden.

"For decades he was the mastermind behind attacks against Americans," Biden said on Aug. 1, also noting the 2000 USS Cole attack and the 1998 bombings of the U.S. embassies in Kenya and Tanzania.

Biden detailed al-Zawahiri's role leading al-Qaida since Osama bin Laden was killed by U.S. forces in 2011, including calling on followers in recent weeks to attack the U.S. and allies in videos.

"We make it clear again tonight that, that no matter how long it takes, no matter where you hide, if you are a threat to our people, the United States will find you and take you out," Biden said.

Biden said that no one else was hurt in the strike, including al-Zawahiri's family, who were elsewhere in a safehouse, and there were no civilian casualties.

An administration official who briefed reporters ahead of Biden's remarks said al-Zawahiri was an active threat to U.S. national security and that his death is a "hugely significant blow" to al-Qaida.

"And to those around the world who continue to seek to harm the United States, hear me now: We will always remain vigilant and we will act and we will always do what is necessary to ensure the safety and security of Americans at home and around the globe," Biden said.

The U.S. has been aware of a network that protected al-Zawahiri for several years, the senior administration official said.

Biden was briefed on the proposed operation, and he convened a meeting on July 25 with key cabinet members and top officials for a final briefing on the intelligence assessment, the official said. There was unanimous support to strike the target and Biden authorized a "tailored" airstrike to minimize civilian casualties.

Zawahiri, an Egyptian eye doctor, had served as bin Laden's deputy before taking over al-Qaida in 2011. But al-Qaida members had complained that he was comparatively uninspiring. The two men fought had together in the war against the Soviets in Afghanistan.

Zawahiri helped found Islamic Jihad, the group that assassinated Egyptian President Anwar Sadat in 1981. Al-Qaida was never able to regain its status as the pre-eminent terrorist organization after bin Laden's death, and faced newer, more brutal, rivals, such as the Islamic State.