A US man has been detained in North Korean custody after crossing the inter-Korean border during a tour without approval. 

The man was taking part in a tour to the Joint Security Area (JSA) at Panmunjom, the border village in the demilitarised zone separating the two Koreas where soldiers from both sides stand guard.

South Korea’s Dong-a Ilbo daily, citing South Korea’s army, reported the person was a US Army soldier.

“A US National on a JSA orientation tour crossed, without authorisation, the Military Demarcation Line into the Democratic People’s Republic of Korea (DPRK),” the UN Command said on Twitter.

“We believe he is currently in DPRK custody and are working with our [North Korea’s People’s Army] counterparts to resolve this incident.”

The US-led UN Command seeks to ensure security on the Korean Peninsula.

Cases of Americans or South Koreans defecting to North Korea are rare, though more than 30,000 North Koreans have fled to South Korea to avoid political oppression and economic difficulties since the end of the 1950-53 Korean War.

Panmunjom, located inside the 248-kilometer-long Korean Demilitarised Zone, was created at the close of the Korean War.

Bloodshed and gunfire have occasionally occurred there, but it has also been a venue for numerous talks and a popular tourist spot.

The area is jointly overseen by the UN Command and North Korea.

In November 2017, North Korean soldiers fired 40 rounds as one of their colleagues raced toward freedom.

The soldier was hit five times before he was found beneath a pile of leaves on the southern side of Panmunjom.

He survived and is now in South Korea.

No civilians live at Panmunjom.

Wires/ABC