SEOUL, South Korea — An unidentified North Korean man crossed the heavily fortified land border separating the two Koreas and is in South Korean custody, the South's military said Friday.
The South's Joint Chiefs of Staff said the military identified and tracked the individual near the central-west section of the military demarcation line and conducted a ''guiding operation'' before taking the person into custody Thursday night.
It said authorities plan to investigate the border crossing and did not immediately say whether they view the incident as a defection attempt.
The Joint Chiefs said it notified the U.S.-led United Nations Command about the incident and had not detected any immediate signs of unusual military activity by the North.
According to the Joint Chiefs, a South Korean military team approached the unarmed North Korean man after detecting him and, after identifying themselves as South Korean troops, guided him safely out of the mine-strewn Demilitarized Zone that divides the two Koreas.
Border tensions have flared in recent months as the two Koreas traded Cold War-style psychological warfare, with North Korea sending thousands of trash-filled balloons toward the South and South Korea blasting anti-Pyongyang propaganda through loudspeakers.
Since taking office last month, South Korea's new liberal President Lee Jae Myung has made efforts to rebuild trust with North Korea, halting the frontline loudspeaker broadcasts and moving to ban activists from flying balloons carrying propaganda leaflets across the border.
In April, South Korean troops fired warning shots to repel about 10 North Korean soldiers who briefly crossed the military demarcation line. The South's military said the soldiers returned to North Korean territory without incident and that the North didn't return fire.