Chung Dong-young urges dialogue after South Korea blames North Korean mines for DMZ blast

South Korean Unification Minister Chung Dong-young called for dialogue and a stable peace regime at a parliamentary audit in Seoul on Oct. 7, after South Korea’s military concluded that North Korean-planted mines caused a Sept. 21 blast in the Demilitarized Zone. Three South Korean soldiers were injured. North Korea denies responsibility, leaving the competing accounts of the blast unresolved.

Chung said the explosion made the need for ‘fundamental peace’ on the Korean Peninsula more crucial. He called for thorough preparation to prevent another such incident but said it would not deter his ministry from seeking peaceful solutions to disputes between the two Koreas. The ministry had reaffirmed its commitment to dialogue the previous day, after the military announced its findings.

What South Korea says caused the DMZ blast

South Korea’s military said on Oct. 5 that its joint investigation with the United Nations Command found resin antipersonnel mines planted south of the Military Demarcation Line by North Korea. Two soldiers suffered critical ankle injuries and a third sustained minor injuries in the Sept. 21 explosion, according to the military account reported by Yonhap.

Joint Chiefs of Staff Vice Chairman Lt. Gen. Kwon Dae-won cited TNT and thermosetting-resin components in the mines. He said fragments recovered from the soldiers matched North Korean plastic mines previously found near the Imjin River. The military said GPS measurements placed two blast sites and a further mine about 10 metres south of the line separating the two sides.

Mine clearance and consultation with the UN Command

South Korea’s Joint Chiefs of Staff said it cleared a minefield south of the Military Demarcation Line near the blast site at about 12:51 p.m. on Oct. 5. It described the clearance as its first operation in response to the blast and said it would continue such operations in the area if North Korea did not voluntarily remove mines Seoul says it planted there.

Kwon called on North Korea to apologize to the injured soldiers and remove the mines. South Korea says their placement violated the armistice. North Korea has denied responsibility for the explosions, while Kim Yo-jong, the sister of leader Kim Jong-un, dismissed Seoul’s findings as a fabrication and warned of retaliation if the South took corresponding action.

At the Oct. 7 audit, Chung said closer consultation with the UN Command was the immediate task in addressing North Korea’s border fortification. The command has jurisdiction over the armistice and, according to Yonhap’s account of Chung’s remarks, says Pyongyang’s mine-planting violates it. Chung did not set out a timetable or a detailed proposal for that consultation.

Why the border works concern Seoul

The Korean War ended in an armistice in 1953. Yonhap’s account of the military briefing says the agreement bars hostile acts within, from or against the DMZ and restricts crossings without authorization from the Military Armistice Commission. Chung said the long-term task was to replace what he called an unstable armistice with a continuous, stable peace system.

Chung warned that North Korea’s fortification could undermine the four-kilometre-wide buffer area around the Military Demarcation Line, which is intended to prevent accidental clashes. Yonhap reported that North Korea began reinforcing fences, laying mines and building anti-tank barriers along the border in April 2024, after Kim Jong-un had described the two Koreas as hostile states the previous year.

South Korea’s Joint Chiefs of Staff said it had seen increasing North Korean activity along the line since March 2025. It estimated that as many as 7,000 troops may have been mobilized daily for land clearing tied to mines and fencing, particularly on the eastern front. These are South Korean military estimates, rather than independently established counts.

The Joint Chiefs also reported more than 50 North Korean crossings south of the Military Demarcation Line in 2026, compared with 17 in 2025 and nine in 2024. The figures add context to Chung’s concern about the buffer area, but the reports do not establish how much of that area the fortifications have affected or what further measures Seoul will take.

Kim Yo-jong said on Sept. 30 that North Korea’s border barriers were an exercise of sovereignty unrelated to any military purpose. Chung’s Oct. 7 remarks kept dialogue at the centre of his ministry’s response, while the announced practical steps remained mine clearance, a demand that the mines be removed, and consultation with the UN Command. No confirmed talks with North Korea were reported.