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An American has crossed the heavily fortified border from South Korea into North Korea, the American-led United Nations Command overseeing the area says, amid heightened tensions over North Korea's nuclear program.
The UN Command tweeted on Tuesday that the US citizen was on a tour to the Korean border village of Panmunjom and crossed the border into the North without authorisation.
It said he was in North Korean custody and that the UN Command was working with its North Korean counterparts to resolve the incident.
It gave no further details on who the person was or why he crossed the border.
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 at home since the end of the 1950-53 Korean War.
Panmunjom, located inside the 248-kilometre-long 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. No civilians live at Panmunjom.
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.
There have been a small number of US soldiers who fled to North Korea during the Cold War, including Charles Jenkins, who deserted his army post in South Korea in 1965 and fled across the DMZ.
He appeared in North Korean propaganda films and married a Japanese nursing student who had been abducted by North Korean agents. He died in Japan in 2017.
In recent years, some Americans have been arrested in North Korea after allegedly entering the country from China.
They were later convicted of espionage and other anti-state acts, but were often released after the US sent high-profile missions to secure their freedom.
In 2018, North Korea released the last three known American detainees as North Korean leader Kim Jong Un was engaged in nuclear diplomacy with then-President Donald Trump. The high-stakes diplomacy collapsed in 2019 amid wrangling over US-led sanctions on North Korea.
Tuesday's border crossing happened amid high tensions over North Korea's barrage of missile tests since the start of last year. The United States earlier on Tuesday sent a nuclear-armed submarine to South Korea for the first time in decades as deterrence against North Korea.
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