AlHijjah 25, 1435, October 19, 2014, SPA -- North and South Korea exchanged gunfire across their heavily fortified border, Seoul's Joint Chiefs of Staff said Sunday. No casualties were reported, according to dpa. South Korean border guards fired warning shots after a group of North Korean soldiers approached the military demarcation line inside the demilitarized zone. This prompted the exchange of fire. This month, troops from both Koreas also exchanged fire after South Korean activists launched balloons carrying pamphlets critical of Pyongyang leader Kim Jong Un. Patrol boats from the two countries also shot at one another after a North Korean navy vessel crossed their maritime border west of the Korean Peninsula, South Korea's Joint Chiefs of Staff said.