A South Korean army staff sergeant died after suffering external injuries at a frontline unit in Cheorwon near the North Korean border on Monday morning, Seoul's Defense Ministry said.
Military and civilian investigators were examining the exact cause and circumstances of his death, the ministry said.
The death comes amid heightened tensions along the border after three South Korean soldiers were wounded in landmine explosions south of the Military Demarcation Line on September 21.
It was not immediately clear whether the staff sergeant’s death on Monday was related to the border tensions.
South Korea's military has said the mines that caused the explosions in September were laid by North Korea as part of its efforts to fortify the border since 2024, an accusation Pyongyang has denied.
This is a developing story.