South Korean military plans to hold field and simulated exercises near the tensely guarded western sea border this week on the second anniversary of North Korea\'s shelling on a border island, Yonhap News Agency said Monday, citing military officials. The Joint Chiefs of Staff (JCS) will conduct a simulated command post exercise and field training under various scenarios of North Korean attacks on Yeonpyeong Island on Friday, the day when the island was hit by some 170 rounds of artillery two years ago, the report said. Two Marines and two civilians were killed in the unprovoked attack. \"Under the host of the JCS, this real-field exercise will be conducted on the day of the attack under various scenarios, such as fire power provocations or an unprovoked attempt to occupy the island, to simulate the combat procedures,\" a Marine Corps official was quoted as saying. This Friday marks the second anniversary of the North\'s bombing of Yeonpyeong Island, which lies just south of the tense Northern Limit Line, a de facto maritime border that the North refused to recognize. The Koreans remain technically in a state of war because the 1950-53 Korean War ended in an armistice, rather than a peace treaty.