South Korean patrol boats fired warning shots on Monday to force North Korean navy vessels back over a disputed maritime border, the South’s military said.
A statement by the South Korean Joint Chiefs of Staff said three North Korean patrol boats had crossed the so-called Northern Limit Line in two separate incidents.
The shots were fired three times in one incident involving two North Korean vessels, the statement said. The North Korean boats did not return fire.
“Three North Korean patrol boats crossed the Northern Limit Line in two locations and retreated back north after warning messages and shots from our navy,” the statement said.
It said there were about 80 Chinese fishing boats in the area at the time. The third North Korean boat retreated after a radio warning, it said.
The latest incursions follow a series of incidents along the frontier between the two Koreas and around the peninsula’s coast.
Last week, South Korean guards found three holes in fences in the Demilitarized Zone. Two fishing boats strayed south before that — one on each coast — and the South also hunted in vain for two North Korean submarines off the south of the peninsula.
Diplomatic sources say the North could be carrying out training for special forces or testing the South’s mettle ahead of Tuesday’s U.S. presidential election.
The Northern Limit Line was drawn by U.S.-led United Nations forces after the 1953 Korean War armistice. Pyongyang has demanded a new sea frontier be drawn far to the south, and in 1999 declared the line invalid.
In mid-June, navy ships from the two Koreas made the first radio communication between active military units since the 1950-53 conflict. It was part of an agreement to reduce tensions in disputed waters off the west coast of the divided peninsula.
But the South has used warning shots since that deal when North Korean vessels failed to respond to radio messages.
Each year, there are disputes in the Yellow Sea, notably at the height of the lucrative crab-fishing season. A long-running disagreement over the inter-Korean sea border has provoked many naval clashes in which dozens have been killed or wounded on both sides.