North Korea's military recently planted land mines along its side of the inter-Korean border, which is prohibited by the inter-Korean armistice agreement signed in 1953.

The United Nations Command(UNC) said on Tuesday that it is aware of the land mine activities by the North's military in the Panmunjeom area, and strongly condemns such acts that endanger thousands of visitors to the demilitarized zone(DMZ).

The UNC said it would not assume why the North Korean military is planting land mines.

A South Korean military source said that North Korea seems to be planting the mines to block potential defection by its own soldiers, rather than to prevent infiltration by the South.

North Korea has replaced old land mines with new ones in the DMZ between May and August every year, but it is known have planted over four thousand land mines this year, in eight locations in the DMZ, which is a two-fold increase from previous years.