A North Korean soldier was taken into custody by South Korean forces from the central area of the heavily fortified inter-Korean border Tuesday evening, the South’s military said the next day.

South Korea’s Joint Chiefs of Staff (JCS) did not provide additional details about the soldier’s identity or background, but told NK News they are currently being investigated.

The lone soldier expressed an intent to defect, Yonhap News reported Wednesday.

While not unprecedented, North Korean military defections directly across the Military Demarcation Line (MDL), the actual border between the two Koreas, are relatively rare compared to the much larger flow