The botched operation was the result of “execution errors combined with confirmation bias and communication breakdowns,” Lt. Gen. Sami Said, the inspector general of the Air Force, said at a press conference Wednesday. The full report is classified to protect sources and methods, according to Said.

Details: 29 individuals were interviewed under oath in the course of the investigation, including 22 directly involved in the strike.

Said said that officials involved in the strike “truly believed at the time that they were targeting an imminent threat,” but that their assessment was “regrettably inaccurate.”

He stressed that the drone strike should be viewed in the context of the environment, in which intelligence showed a “very high” threat to U.S. forces in the wake of an ISIS-K bombing that killed 13 U.S. service members and 170 Afghan civilians at Kabul’s airport on Aug. 26.