S Korea fires warning shots after N Korea soldiers briefly cross border

South Korean troops fired warning shots after North Korean soldiers briefly crossed the border this week, Seoul's military said Tuesday, with tensions high over Pyongyang's barrage of trash-carrying balloons and the South's retaliatory loudspeaker campaign.

The Sunday incursion over the line that separates the two militaries took place in an overgrown area of the heavily fortified border area and was likely accidental, the Joint Chiefs of Staff said.

Relations between the two Koreas — technically still at war as the 1950-1953 conflict ended in an armistice rather than a peace treaty — are at one of their lowest points in years.

"Some North Korean soldiers working within the DMZ on the central front briefly crossed the Military Demarcation Line (MDL)," the JCS said in a statement, referring to the line of control between the two Koreas.

"After our military issued warning broadcasts and warning shots, they retreated northward," it said, adding there had been "no unusual movements observed" subsequently.

About 20 North Korean soldiers crossed the border, according to the Joint Chiefs of Staff.

The incursion was likely accidental, JCS spokesperson Lee Sung-joon told reporters Tuesday.

"The situation at that time was that the DMZ was now overgrown with trees and the MDL mark was not clearly visible," Lee said.

"There was no road, and the (North Korean soldiers) were moving through the bushes, and we were observing (them) even before they got close to the MDL.

"We believe that they did not intend to invade, considering that they immediately moved northward after the warning broadcasts and warning shots."

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