A US drone strike took out multiple suicide bombers as part of an “imminent ISIS-K threat” to the Kabul airport Sunday as officials raced against the clock to wrap up evacuation efforts in Afghanistan, US officials said. The strike successfully knocked out a vehicle packed with a “substantial amount of explosive material,” Capt. Bill Urban, spokesman for the US Central Command, said in a statement. “U.S. military forces conducted a self-defense unmanned over-the-horizon airstrike today on a vehicle in Kabul, eliminating an imminent ISIS-K threat to Hamad Karzai International airport,” Urban said. “We are confident we successfully hit the target.” “Significant secondary explosions from the vehicle indicated the presence of a substantial amount of explosive material,” he added. Witnesses said the drone strike had targeted two cars parked in a residential building near the airport. It is unclear if either of the vehicles were meant to be a car bomb or intended to transport the suicide bomber, a source told CNN. But one of the cars was “loaded up and ready to go,” the source said.