Seoul: South Korea fired warning shots on Friday after a North Korean patrol boat crossed a disputed maritime border to the west of the divided peninsula, the South`s military said.
Such incidents are not unheard of along the tense sea border between the rivals but it came on the day that the Asian Games officially opened in the South, with North Korean athletes participating.
A South Korean Defense Ministry official said the North Korean vessel intruded into waters controlled by the South off Baengnyeong island just after noon but it turned back six minutes after the South Korean navy fired warning shots.
The two Koreas are technically still at war after their 1950-53 conflict ended in a truce and not a peace treaty and their border is one of the most heavily militarised in the world.
The disputed western waters are the most volatile area of the border. Four years ago, North Korea shelled a South Korean island in the region, killing four people. Last year, the two sides fired hundreds of artillery shells into each other`s waters.
South Korean President Park Geun-hye told Reuters in an interview this week that the door was open for talks with the North during the upcoming U.N. General Assembly session.
But Park said the North must show sincerity in seeking constructive dialogue and "walk the talk" in taking up South Korea`s offers for engagement aimed at ending a deadlock after a decade of warming ties.
South Korea`s military said on Monday it had recovered the wreckage of an unmanned aircraft, believed to be a North Korean drone, in waters off Baengnyeong island.