Pyongyang dismissed findings by Seoul that North Korean forces planted landmines that wounded three South Korean troops last week, with the influential sister of leader Kim Jong Un threatening military retaliation should South Korea target her country’s border workers.
The troops suffered wounds during two consecutive blasts on 21 September close to the military demarcation line within the western sector of the Demilitarized Zone, the heavily fortified buffer separating the rival nations.
The remarks from Kim Yo Jong came after South Korea’s Joint Chiefs of Staff presented a preliminary investigation conducted alongside the US-led UN Command concluding that North Korean explosives caused the detonations.
South Korean and UN investigators subsequently found another mine during searches on Tuesday, leading the UN Command to confirm that North Korea had breached the armistice agreement that halted hostilities in the 1950-53 Korean War.
The command said it was addressing the breach through established mechanisms without offering further specifics.
South Korean defence minister Kang Shin Chul warned that Seoul would evaluate “corresponding measures” if an inquiry formally established North Korean accountability for the incidents.
Denouncing the South Korean findings as a "conspiratorial farce", Ms Kim, considered the second most powerful figure in North Korea, accused Seoul of fabricating a pretext for border provocation.
In recent years, North Korea has heavily reinforced its frontline defences by deploying landmines and anti-tank barriers amid deteriorating inter-Korean relations, stoking alarm in Seoul over the growing concentration of personnel along the heavily monitored frontier.
In a televised address, Kang Hyunwoo, chief director of operations for the South Korean Joint Chiefs of Staff, stated that the military "strongly urges" Pyongyang to offer an apology for the explosions and enact "responsible measures" to prevent future occurrences while demanding an immediate halt to border fortification efforts.
"We clearly state that North Korea bears full responsibility for any future developments," he said.
Ms Kim defended the construction work as a legitimate exercise of national sovereignty aimed at reinforcing the border and accused Seoul of heightening tensions through warning broadcasts and live fire directed near her country’s troops, asserting that "our soldiers have never crossed the border”.
"When a single bullet is hit on our land, they must be prepared for a lot," she said. If the South Korean “military gangsters fire at our soldiers carrying on the permanent project for the southern border, not warning shots, our border units will take immediate and merciless retaliatory action”, she added.
The detonations occurred roughly 10 metres south of the demarcation line as South Korean troops worked to construct a new patrol path through dense vegetation untouched for decades. The initiative aimed to facilitate joint surveys with the UN Command following shifts in terrain detected last year that hinted at northern minelaying activity.
Kwon Dae Won, vice chairman of the Joint Chiefs of Staff, noted a "very high possibility" that North Korean mines caused the blasts, pointing out that neither southern nor allied forces had records of laying explosives in the area. Forensic evidence, blast signatures, and a third suspected northern mine reinforced the conclusion, while Mr Kang noted that a potential fourth mine was detected on Tuesday.
Spanning 248km in length and 4km in width, the DMZ is one of the world’s most heavily militarised frontiers, protected by some two million buried landmines alongside razor wire, anti-tank obstacles, and stationed troops.
The DMZ serves as a lasting legacy of the Korean War, which concluded with a ceasefire rather than a permanent peace treaty.
The recent explosions echoed an incident from over a decade ago when Seoul attributed landmine blasts in 2015 to the North after two South Korean soldiers were severely maimed, precipitating a sharp escalation in regional tension.
That crisis saw both nations exchange threats, conduct military displays, and resume cross-border propaganda broadcasts before intense negotiations defused the stand-off.
Pyongyang eventually issued a vague expression of regret over the injuries without formally admitting responsibility.
The recent blasts coincide with efforts by South Korea’s liberal administration to restart diplomatic dialogue between Pyongyang and Washington, as part of a push to ease military tensions across the Korean Peninsula.
North Korea has adopted an increasingly aggressive stance since 2024, designating South Korea as a permanent adversary and discarding long-standing goals of eventual unification in favour of a hostile, two-state doctrine.
Pyongyang continues to reject American overtures to resume negotiations that stalled in 2019, maintaining that Washington must abandon demands for northern denuclearisation before any discussions can take place.
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