ELLSWORTH AIR FORCE BASE, S.D. -- Staff Sgt. Mark Sidle, 28th Security Forces Squadron dog handler, apprehends Tech. Sgt. Aaron Hazen, 28th Bomb Wing NCO in charge of the executive client support team, during an active-shooter exercise, April 15. The purpose of the exercise was to test the total reaction and response time of the 28th BW. (U.S. Air Force photo/Senior Airman Adam Grant)