North Korea carried out live-fire artillery exercises near the maritime border with the South, dpa quoted South Korea's Joint Chiefs of Staff as saying Tuesday. North Korean forces began firing shells at 2pm (0500 GMT), the Yonhap News Agency reported. "We are carefully monitoring North Korea's exercise to sternly react if any of its shells fall in southern waters," said Kim Min Seok, a spokesman for the Defence Ministry in Seoul. The Korean People's Army announced the drills in a fax to the South Korean Navy's Second Fleet, Yonhap reported. The drill took place near Baengnyeong Island, the Korean Broadcasting System quoted the South's Joint Chiefs of Staff as saying.