Three South Korean soldiers have been injured in an explosion at the heavily fortified border with North Korea.
South Korean President Lee Jae Myung said the blast was caused by a landmine while the soldiers were clearing a route in the demilitarised zone (DMZ).
The DMZ has separated the Koreas since the end of the Korean War in 1953 and is covered in barbed wire, landmines and extensive surveillance.
It comes after reports claimed North Korea had carried out more work in the zone earlier in the year.
Two of the soldiers were receiving treatment after being evacuated by helicopter, the South Korean military said.
The third was being transferred to hospital for medical examinations, along with others who took part in the operation.
Officials have not provided any further details on the condition of the injured soldiers.
The explosion took place south of the military demarcation line within the DMZ, South Korean officials said.
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The DMZ, which is 155 miles long and 2.5 miles wide, is one of the world's most heavily armed borders and is covered by an estimated two million mines.
North Korean forces resumed fortification work near the border in March, including more landmines and fence construction, according to reports.
Earlier this month, South Korean lawmaker Yu Yong-weon said minefields and other installations built by North Korea crossed the military demarcation line by roughly 10 to 15 metres (33-49 ft) at six locations in the western area of the DMZ, Reuters news agency reported.
(c) Sky News 2026: Three South Korean soldiers injured in landmine border explosion
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