Barksdale Defenders run and gun for active shooter training
Senior Airman Kyle Harper, 2nd Security Forces Squadron entry controller, sights his rifle at Barksdale Air Force Base, La., July 18, 2016. During the training, defenders cleared the building room by room, looking for the shooter. Once all threats had been neutralized, the teams execute a second building sweep to make sure no threats were left behind. (U.S. Air Force photo/Senior Airman Curt Beach)