South Korea's military seized a North Korean fishing boat that crossed the maritime border between the two Koreas on Tuesday and fired a warning shot to see off a North Korean patrol vessel that tried to intervene, the Yonhap news agency reported.
The seized boat was carrying seven crew, including six wearing military uniforms. The seven unarmed North Koreans are said to have no intention of defecting to the South and claim their ship accidentally veered into South Korean waters, Yonhap said.
Seoul has sent messages to the North about the border crossing incident two times thorough commercial and military communication lines, according to the South Korean military.
Border incidents between the two Koreas are closely watched by both countries, which have officially been in a state of war since the 1950-53 Korean War ended with an armistice not a peace treaty.
The North Korean fishing boat crossed the border at around 9:30 a.m. off the west coast of the peninsula and was then seized and towed to South Korea's Baengnyeongdo island for investigation, Yonhap said, citing the Joint Chiefs of Staff.
The South Korean military fired a warning shot at a North Korean patrol boat that briefly crossed the border while tracking the fishing boat, it said.
South Korea's Defense Ministry did not immediately respond to a request for comment.