What did South Korea’s military say caused the DMZ explosion near the Military Demarcation Line?

The military said it was highly likely that a North Korean mine caused the blast. It said North Korea would bear full responsibility if the final investigation confirms the mines were planted there.

When did the DMZ blast happen and who was hurt?

The incident took place on Sept. 21 during a route-clearance operation in the DMZ. Two soldiers were seriously injured and a third suffered minor injuries while 18 troops were working on the route.

What evidence did the military cite in its investigation of the DMZ explosion?

The military cited a forensic finding of TNT and brown-colored foreign material on protective gear, the lack of metal fragments, no South Korean mine-laying records in the area, and a witness account of a suspected unexploded mine near the blast site. It also said the object resembled a North Korean wooden-box mine but may have been a plastic anti-personnel mine.

Military says NK mine almost certainly caused DMZ blast, vows response

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Summary

South Korea’s military said Monday that a North Korean mine was highly likely to have caused last week’s explosion in the Demilitarized Zone, and it vowed corresponding measures. The blast injured South Korean soldiers during route-clearing work south of the Military Demarcation Line. A joint investigation with the U.N. Command is continuing.

Key Facts

The Sept. 21 incident happened while 18 soldiers were clearing a new search route for the United Nations Command to inspect suspected North Korean mine-laying activity near the Military Demarcation Line.
Two mines exploded during the operation, seriously injuring two soldiers and leaving another with minor injuries.
Fifteen of the 18 personnel have been discharged from the hospital, while three injured soldiers remain hospitalized.
A preliminary forensic examination found TNT and brown-colored foreign material on the soldiers’ protective equipment, but no metal fragments.
The military said a joint investigation with the U.N. Command is continuing, and further field inspections are planned before final findings are released.

By Bahk Eun-ji

Published Sep 28, 2026 9:02 pm KST
Updated Sep 28, 2026 10:20 pm KST

Joint Chiefs of Staff Vice Chairman Kwon Dae-won briefs reporters on the suspected DMZ mine explosion at the defense ministry headquarters in Yongsan District, Seoul, Monday. Yonhap

South Korea’s military said Monday it is highly likely that a North Korean mine was almost certainly responsible for last week’s explosion in the Demilitarized Zone (DMZ), holding Pyongyang responsible and announcing plans for corresponding measures.

“Based on our overall assessment of the investigation and field inspection so far, we have determined that the explosion was highly likely to have been caused by a North Korean mine,” Joint Chiefs of Staff (JCS) Vice Chairman Lt. Gen. Kwon Dae-won said during an evening briefing at the defense ministry in Seoul.

Kwon said North Korea would bear full responsibility if the final investigation confirms that the North planted the mines that injured South Korean troops who were conducting operations south of the Military Demarcation Line (MDL).

“Our military will take appropriate and corresponding measures,” he said.

The Sept. 21 incident occurred as 18 soldiers were clearing a new search route to allow the United Nations Command (UNC) to inspect terrain changes suspected to be linked to North Korean mine-laying activity near the MDL.

Two mines exploded during the operation, seriously injuring two soldiers and leaving another with minor injuries. All 18 personnel were airlifted to the Armed Forces Capital Hospital. Fifteen have since been discharged, while the three injured soldiers remain hospitalized.

The JCS said the blasts occurred about 10 meters south of the MDL, roughly 10 meters from where signs of suspected North Korean mine-laying were found in September 2025.

A preliminary forensic examination by the National Forensic Service detected TNT and brown-colored foreign material on the soldiers’ protective equipment, but no metal fragments.

Maj. Gen. Yang Jin-hyuk, the JCS director of operations, said the findings, combined with the relatively limited blast radius, indicated that the explosives were not South Korean mines.

The military also cited the absence of South Korean mine-laying records in the area and witness accounts of a suspected unexploded mine discovered about 1 meter from the blast site.

Yang said the object resembled a North Korean wooden-box mine in shape but was believed to be a plastic anti-personnel mine. Its type has yet to be confirmed through physical examination.

The military believes three mines may have been present at the site, including the suspected unexploded device.

However, the military has yet to establish when or how the mines reached the area, leaving open the possibility that they had been displaced from elsewhere.

A joint investigation with the UNC remains underway, with further field inspections planned before the final findings are released.

Asked about possible responses, Yang said the military would consider all available options after completing the investigation.

“The JCS will consider all necessary military options, while the defense ministry will examine policy options,” he said.

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