A North Korean man crossed the inter-Korean border and defected to South Korea on Tuesday, officials said Wednesday.

The 21-year-old defector, identified only by his surname Kim, immediately expressed his wish to defect to the South after he crossed the Military Demarcation Line in the Demilitarized Zone and was spotted at around 5 p.m. by South Korean troops standing guard around the frontline areas.

Government authorities are currently investigating him to find out the exact reasons for his defection.

Some officials said he risked the perilous defection due to the deepening food crisis in the impoverished state, pointing out that it will take several days until the investigation results come out.

It was reported that Kim was expelled from the North Korean military after he was classified as “unqualified” to become a soldier, and that he had yearned for life in the South.

It was the first time for a North Korean to defect to the South after crossing the heavily-fortified land-based border since a North Korean non-commissioned officer defected to the South last March.

More than 20,000 North Koreans have defected to the South since the end of the 1950-53 Korean War.

By Song Sang-ho (sshluck@heraldcorp.com)