Republic of Korea Marines demonstrate a minesweeping technique for U.S. Marines April 21 during Korean Marine Exchange Program 14-6 in Pohang, Republic of Korea. Marines use metal detectors to help identify improvised explosive devices, landmines or anything potentially harmful that is buried underground. The ROK Marines are with the 1st ROK Marine Engineer Battalion, 1st ROK Marine Division. The U.S. Marines are with 9th Engineer Support Battalion, 3rd Marine Logistics Group, III Marine Expeditionary Force.