Tech. Sgt. Martin Evans, 28th Security Forces Squadron flight chief, and Officer Glenn Waters, 28th SFS senior police officer, coordinate and establish a cordon following a simulated bomb threat during an Operational Readiness Exercise at Ellsworth Air Force Base, S.D., March 16, 2012. Simulated emergencies tested the ability of Airmen to respond quickly and appropriately likely event scenarios. (U.S. Air Force photo by Airman 1st Class Kate Thornton/Released)