INFRAME ASIA, NEWS – South Korea’s military said on October 5, 2026, that North Korea deliberately planted two landmines inside the Demilitarized Zone (DMZ), causing an explosion that injured three South Korean soldiers. The conclusion followed a joint investigation involving South Korea’s military and the United Nations Command. Seoul said the findings confirmed its earlier assessment that the mines originated from North Korea.
The explosions occurred on September 21, 2026, in the western section of the DMZ. The three South Korean soldiers were conducting an operation to prepare a patrol route when the mines detonated. Two soldiers suffered serious injuries to their ankles, while the third sustained minor injuries.
South Korea’s Joint Chiefs of Staff said investigators found evidence linking the explosives to North Korean mines. The devices contained TNT and thermosetting resin components consistent with North Korean anti-personnel mines. Fragments recovered from the injured soldiers were also found to be identical to North Korean plastic mines previously recovered from the Imjin River.
Investigators also examined the precise location of the explosions. According to South Korea’s military, the two blast sites were located about 10 meters south of the Military Demarcation Line, rather than on the North Korean side of the border. The location was cited as evidence that the mines had been deliberately placed there rather than washed into the area by flooding.
A further mine was discovered close to one of the explosion sites during the investigation. South Korean investigators said the additional device was the same type of North Korean resin anti-personnel mine identified through forensic analysis. The United Nations Command reached the same assessment regarding the origin and placement of the mines.
The South Korean military said North Korea has been reinforcing its border defenses since April 2024. The work has included installing mines, strengthening barbed-wire fences and constructing anti-tank barriers along the Military Demarcation Line. Seoul said the fortification activity has expanded along the length of the inter-Korean border.
South Korea also said North Korea has deployed large numbers of personnel for the border construction work. The military estimated that as many as 7,000 North Korean workers had been involved in the activities this year. Seoul also reported more than 50 incidents in which North Korean personnel crossed south of the Military Demarcation Line during 2026.
The latest investigation led South Korea to begin removing additional mines from the area. On October 5, 2026, at around 12:51 p.m., South Korean forces carried out an operation to detonate and clear mines located south of the Military Demarcation Line. The military said further mine-removal operations would continue if North Korea did not remove the devices itself.
South Korea demanded that North Korea apologize to the three injured soldiers and remove mines that Seoul said had been planted in violation of the Korean War Armistice Agreement. Lieutenant General Kwon Dae-won, vice chairman of the Joint Chiefs of Staff, said the mines had been placed in an area where hostile acts are prohibited under the armistice. The agreement ended active fighting in 1953, but did not establish a formal peace treaty between the two Koreas.
North Korea has rejected South Korea’s accusation. Pyongyang has denied responsibility for the September 21 explosions and dismissed Seoul’s investigation as fabricated. Kim Yo Jong, the sister of North Korean leader Kim Jong Un, has also warned that North Korea could take retaliatory action if South Korea responds militarily to its border activities.
