160505-N-WT427-135 BUSAN, Republic of Korea (May 05, 2016) Sailors assigned to Commander, U.S. Naval Forces Korea (CNFK) participate in a Chemical, Biological and Radiological (CBR) defense course. CNFK is the U.S. Navy's representative in the Republic of Korea, improving institutional and operational effectiveness between the two navies and strengthening collective security efforts in Korea and the region. (U.S. Navy photo by Mass Communication Specialist 3rd Class Jermaine M. Ralliford/Released)