The South's Joint Chiefs of Staff were checking on the accusation that comes after North Korea in recent months has threatened to reduce its rich neighbour to ashes in anger at Seoul's hardline policies.
"The reckless provocation perpetrated at a time when the military confrontation between the North and the South has reached an extreme phase is a vicious criminal act of seriously getting on the nerves of the servicepersons of the Korean People's Army and lashing them into a great fury," the North's official KCNA news agency said.
The North demanded the South to move the marker.
The Korean peninsula is divided by a four-km wide Demilitarised Zone (DMZ) buffer that was put in place after the 1950-53 Korean War ended in a ceasefire.
The actual border between the two states technically still at war is a sparsely marked line within the no man's land DMZ.
The United States stations about 28,000 troops in South Korea to support its 670,000 soldiers. The North positions most of its 1.2 million troops near the border with its capitalist neighbour.
Source: FOCUS Information Agency
