Al Qaeda Leader Ayman al-Zawahiri Dead After U.S. Drone Strike in Afghanistan: 'Justice Delivered'

An al Qaeda leader who was associated with Osama bin Laden and "deeply involved" with the 9/11 attacks is now dead after the U.S. carried out a missile strike in Afghanistan, President Joe Biden announced on Monday.

In a speech on the attack captured by NBC News, Biden, 79, said, "On Saturday, with my direction, the United States successfully concluded an air strike in Kabul, Afghanistan," killing Ayman al-Zawahiri, 71.

He said al-Zawahiri was "bin Laden's leader, his deputy at the time the terrorists attacked 9/11. He was deeply involved in the planning of 9/11," which killed nearly 3,000 people. Biden also said "for decades" al-Zawahiri "was the mastermind behind attacks" that killed and injured thousands of Americans.

Al-Zawahiri took over al Qaeda after bin Laden was killed in a U.S. strike in May 2011, Biden said in Monday's speech.

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"Since the United States delivered justice against bin Laden 11 years ago, Zawahiri has been a leader of al Qaeda, the leader. From hiding, he coordinated al Qaeda's branches, and all around the world provided operational guidance that called for and inspired attacks against U.S. targets," said Biden.

Continued the president: "He made videos including in recent weeks, calling for his followers to attack United States and our allies. Now, justice has been delivered, and this terrorist leader is no more."

Sending a pointed message, Biden, who is isolated with his second bout of COVID-19 in a month, added: "People around the world no longer need to fear the vicious and determined killer. The United States continues to demonstrate our resolve and our capacity to defend the American people against those who seek to do us harm. We make it clear again tonight, 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."

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Biden said former Presidents George W. Bush, Barack Obama, and Donald Trump had been on the hunt for al-Zawahiri before he was found earlier this year as he relocated to downtown Kabul "to reunite with his family." Biden said after confirming his whereabouts, "I authorized a precision strike that would remove him from the battlefield once and for all."

"This mission was carefully planned rigorously to minimize the risk of harm, and one week ago, after being advised the conditions were optimal, I gave the final approval to go get him. And the mission was a success."

Al-Zawahiri's relatives were not injured in the attack and there were "no civilian casualties," Biden said.

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Remembering those who lost their lives on Sept. 11 over 20 years ago, Biden ended his speech by stating, "We continue to mourn every innocent life that was stolen on 9/11 and honor their memories.

"To the families who lost fathers and mothers, husbands, wives, sons and daughters, brothers and sisters, friends and coworkers on that searing September day, it is my hope that this decisive action will bring one more measure of closure."

Biden was told about al-Zawahiri's location in April, before being given a potential attack plan early last month, an administration official told reporters, per ABC News.

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"The president received an updated operational report and pressed at a granular level. He asked again about any other options that would reduce collateral or civilian casualties. He wanted to understand more about the layout of rooms [of al-Zawahiri's safe house in Kabul] behind the door and windows on the third floor of the building," they said, according to the outlet.

"At the conclusion of the meeting, the president authorized a precise tailored airstrike on the condition that a strike minimize to the greatest extent possible the risk of civilian casualties. This authorization meant that the U.S. government could conduct an airstrike once an opportunity was available," the official said.