A responder prepares a simulated casualty for emergency medical treatment during an active shooter exercise at Holloman Air Force Base, N.M., Feb. 26. The active shooter exercise tested the threat response time and effectiveness of Holloman AFB's first responders. The 49th Security Forces Squadron members' secondary mission was tending to the simulated casualties until emergency medical personnel arrived. (U.S. Air Force photo by Senior Airman DeAndre Curtiss)