Barksdale Defenders run and gun for active shooter training
Senior Airman Kyle Harper, 2nd Security Forces Squadron entry controller, prepares for an active shooter exercise at Barksdale Air Force Base, La., July 18, 2016. During the training, defenders clear a building room by room, looking for the shooter. Once the shooter has been located and neutralized, the team does a second building sweep to make sure no threats remain. (U.S. Air Force photo/Senior Airman Curt Beach)