“North Korea has detonated part of the Gyeonggi-Donghe Road north of the Military Demarcation Line,” the committee said Tuesday, referring to the cross-border infrastructure that once connected the two countries.
“Our military forces were not harmed and our forces returned fire in areas south of the military demarcation line,” it added.
The roads have long been closed, but their destruction is a clear signal that North Korea’s authoritarian leader, Kim Jong-un, is not ready for talks with the South, experts say.
Relations between the two Koreas have hit their lowest point in years, and last week North Korea’s military said it would permanently close the southern border, “completely cutting off roads and railways” connecting the south and building “strong defense structures”.
The fact that North Korea is preparing to blow up the roads connecting the two countries on its side of the border was announced on Monday by Lee Song-jun, the representative of the South Korean Joint Chiefs of Staff for press relations.
Tensions on the Korean Peninsula have increased for several weeks.
North Korea has accused South Korea of using drones three times to drop propaganda leaflets over North Korean territory and has threatened to respond with force if it happens again.
North Korea’s defense ministry said in a statement on Sunday that it had deployed several army units to the border and was “fully preparing to open fire” and that South Korea would “turn into piles of ashes” if attacked.
South Korea’s Unification Ministry spokesman Gu Byeong-sam said the move was likely motivated by a desire to strengthen North Korean unity by focusing on a common enemy.
Pyongyang often uses belligerent rhetoric in preparation for missile tests, which it has been banned from conducting by the United Nations.
Experts say a full-scale attack is unlikely given the superior firepower and numerical superiority of South Korea and its ally the United States.
However, the destruction of cross-border roads could be a major blow to decades of work towards a peaceful reunification of the two countries.
Last January, the North Korean dictator amended the constitution, removing language on reunification, and declared the South his “unchanging arch-enemy”.