OSAN AIR BASE, Republic of Korea -- 51st Security Forces Squadron and Republic of Korea Air Force members performed base defense operations training during the combat readiness course at Osan Air Base, June 26. During training, combined SF members reacted to simulated hostile forces. Members were challenged with securing Base Alpha, executing troop movement maneuvers and communication tactics. Security Forces members are responsible for ensuring the safety of bases, weapons, property and personnel from hostile forces. (U.S Air Force Photo by/Staff Sgt. Daylena Gonzalez)