Medical staff at the Armed Forces Capital Hospital are treating personnel who were wounded in an explosion inside the Demilitarized Zone on Sept. 21. The South Korean military confirmed 3 soldiers were hurt in the suspected mine blast south of the Military Demarcation Line, including 2 who are in serious condition.

The source of the explosive device has not been determined. It remains unclear if the mine was planted by North Korean forces or if it was a legacy piece of equipment belonging to the South Korean military.