North Korean DMZ landmine blast 'violation of armistice'

South Korea's defence chief said Tuesday that the preliminary findings of an investigation into last week's landmine explosion inside the Demilitarised Zone found North Korea responsible, saying the blast violated the armistice agreement.

The September 21 blast injured three South Korean troops, one of whom lost a foot, inside the DMZ, the heavily mined buffer zone dividing the two Koreas.

The minister's comments came a day after the defence ministry said North Korean mines were "highly suspected" of causing the two explosions last week.

"This is a clear violation of the armistice agreement, and since North Korea bears responsibility, we will take corresponding measures," Defence Minister Kang Shin-chul told a parliamentary hearing on the explosion.

While the DMZ itself is officially demilitarised, its northern and southern boundaries are among the world's most heavily fortified frontiers and remain littered with landmines.

At Tuesday's hearing, Yang Jin-hyeok of the Joint Chiefs of Staff told MPs Tuesday that a site investigation earlier in the day discovered an unexploded North Korean plastic anti-personnel mine.

Minister Kang told MPs the military "have a range of necessary measures at our disposal, and we will implement them in stages", without giving details.

Seoul and Pyongyang remain technically at war since the Korean conflict ended in a truce, not a peace treaty.