President Joe Biden announced Monday that a weekend airstrike in Afghanistan killed al-Qaida leader Ayman al-Zawahri.

“He carved a trail of murder and violence against American citizens, American servicemembers, American diplomats and American interests,” Biden said of the terrorist leader, who he referred to as “the emir of al-Qaida.”

The Associated Press was first to report the successful strike, which a senior administration official told reporters took place at 9:48 p.m. ET on Saturday, which was early in the morning of Sunday at the al-Zawahri safe house in downtown Kabul.

“After carefully considering the clear and convincing evidence of his location, I authorized the precision strike that would remove him from the battlefield once and for all. This mission was carefully planned, to rigorously minimize the risk of harm to other civilians,” Biden said. “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. None of his family members were hurt, and there were no civilian casualties.”

In what the official described as “a precision counterterrorism operation,” two hellfire missiles were fired from an unmanned aerial vehicle, taking out al-Zawahri on a balcony.

Biden was briefed on a proposal for an operation on July 1 by senior intelligence and national security officials, according to the official. After that, the official told reporters, the president personally reviewed details of the operation to try to “minimize” the risk of civilian casualties, including reviewing the building plans and receiving additional details in the ensuing weeks.