North Korea fired around 130 artillery shells into the sea off its eastern and western coasts on Monday, the South Korean military said, in the latest apparent military exercise near their shared border. .
Some of the shells landed in a buffer zone near the maritime border, in what Seoul said was a violation of a 2018 inter-Korean agreement designed to reduce tensions.
The South Korean military sent several communications warning the North about the shooting, the Defense Ministry said in a statement.
North Korea did not immediately report the artillery fire, but has been carrying out an increasing number of military activities, including missile launches and drills by warplanes and artillery units.
South Korea and the United States have also intensified military drills this year, saying they are necessary to deter the North, which has nuclear weapons.
The 2018 Comprehensive Military Agreement was the most substantive deal to emerge from months of meetings between leader Kim Jong-un and then-South Korean President Moon Jae-in.
However, with those talks long stalled, recent drills and shows of force along the fortified border between the Koreas have cast doubt on the future of the measures. South Korea has accused the North of repeatedly violating the agreement with artillery exercises this year.
This year North Korea resumed testing its long-range intercontinental ballistic missiles (ICBMs) for the first time since 2017, and South Korea and the United States say they have made preparations to resume nuclear tests as well.