Two South Korean soldiers have been seriously injured in a suspected mine blast at the border with North Korea, state media report.
The Yonhap news agency said the explosion happened as the soldiers were on a search mission in the heavily fortified demilitarised zone (DMZ).
The soldiers sustained serious leg wounds but were not in a critical condition, it said.
An army official ruled out North Korean involvement.
The 4km (2.5 mile)-wide DMZ is one of the world’s most protected borders, separating the two Koreas which remain technically at war.