An explosion near South Korea's heavily fortified border with North Korea has injured three South Korean military officers, Seoul has said.
South Korea's Defence Ministry said on Monday that the explosion occurred during an unspecified operation in the Demilitarised Zone, a border buffer zone separating the two nations that is commonly referred to as the DMZ.
The cause was not immediately clear, the ministry said.
Officials did not say whether the explosion could have been caused by a landmine planted by North Korea, which has added mines, anti-tank barriers and other frontline fortifications in recent months as relations between the two countries have sharply deteriorated.
Two of the officers were airlifted from the site by helicopter, while the third was transported by land before being airlifted, according to the ministry. The officers are being treated at a military hospital near the capital Seoul.
The DMZ, which stretches 248 kilometres and is four kilometres wide, is one of the world’s most heavily armed borders. An estimated two million mines lie inside and near the border alongside barbed wire fences, tank traps and combat troops on both sides.
The zone is a legacy of the 1950–1953 Korean War, which ended with an armistice but no peace treaty.
Border tensions
Increased activity by North Korean soldiers near the military demarcation line has raised concerns in South Korea as Pyongyang strengthens its border defences amid prolonged tensions.
The South Korean military has not officially confirmed media reports that North Korean soldiers crossed the line more than 20 times during frontline operations in August alone.
In April 2025, South Korean troops fired warning shots after around 10 North Korean soldiers crossed the line in the eastern section of the DMZ. The North Korean soldiers retreated following audio warnings and the shots, with no clashes reported.
North Korean troops also crossed the border three times in June 2024, prompting South Korea to fire warning shots.
North Korean leader Kim Jong-un has suspended virtually all cooperation and diplomacy with Seoul in recent years, declaring South Korea his country’s most hostile enemy amid a stalemate in nuclear negotiations with Washington.
Landmines have caused casualties on the southern side of the border before. North Korean mines have occasionally washed down swollen rivers into South Korea, killing or injuring civilians.
In August 2015, landmine blasts maimed two South Korean soldiers and triggered a sharp rise in tensions between the two countries.
