Security Forces defends headquarters
U.S. Air Force Staff Sgt. Lenjie Olbrantz, 51st Security Forces Squadron operations center controller, searches Staff Sgt. Nick Ruttencutter, 51st Security Forces Squadron defender, a simulated enemy, for extra ammunition during a surprise exercise at Osan Air Base, Republic of Korea, May 4, 2017. The exercise was held to examine how well personnel could defend the base in response to a surprise attack. (U.S. Air Force photo by Tech Sgt. Ashley Tyler/Released)