North Korea Denies DMZ Mine Blast, Warns South Korea

North Korea on Wednesday, Sept. 30, 2026, rejected South Korea’s finding that a Northern land mine likely caused a recent Demilitarized Zone blast, issuing a sharp North Korea DMZ mine denial and warning of “immediate and merciless” retaliation if Southern troops fire on its border units.

Kim Yo-jong, sister of leader Kim Jong-un, said in a KCNA statement that Seoul is “cooking up the groundless results” to justify provocation. The blast on Sept. 21 injured three South Korean soldiers inside the DMZ.

North Korea DMZ mine denial follows Seoul probe

South Korea’s Joint Chiefs of Staff said Monday that North Korean mines were “highly likely” responsible and later released a photo of a resin antipersonnel mine found near the site. Defense Minister Kang Shin-chul warned Seoul would take “corresponding measures” if the finding is confirmed, Yonhap reported.

The U.N. Command, which oversees the armistice area, has said the explosion violated the Armistice Agreement that ended the 1950–53 Korean War—an assessment first detailed when South Korea and the UN Command probed the DMZ blast site.

Kim Yo-jong threatens tactical countermeasures

Kim claimed Northern barrier work along the southern border is a sovereign exercise unrelated to military purposes and insisted Northern soldiers “have never crossed the border.” She accused South Korean forces of threatening them with broadcasts and shots.

“If the ROK military gangsters fire at our soldiers … our border units will take immediate and merciless retaliate attack,” she said, adding that the army decided to increase “tactical counterattack means” near South Korea’s 21st Infantry Division and that counteraction principles had already been issued to border units.

Border fortification and MDL crossings rise

Pyongyang has been fortifying the inter-Korean border since April 2024—barbed wire, mines, and anti-tank barriers—after Kim Jong-un declared the two Koreas hostile states. South Korean authorities said Northern troops crossed the Military Demarcation Line more than 20 times last month alone, exceeding all of 2025.

Kang told lawmakers Tuesday that mines appeared planted at “several locations” south of the MDL. On Wednesday the JCS urged Pyongyang to apologize and take responsibility, saying the North “bears full responsibility for any future consequences.” The confrontation also sits against recent North Korean weapons signaling, including tests of upgraded 240mm guided rockets.

Risk of miscalculation on the eastern front

Analysts note Kim’s reference to the 21st Infantry Division points to the eastern front, not the western sector where the Sept. 21 blast occurred—suggesting Pyongyang may be broadening its threat geography. With both sides hardening the frontier and Seoul promising “corresponding measures,” the DMZ dispute adds another flashpoint on a peninsula already tense over nuclear signaling and alliance diplomacy.