An American soldier has been detained by North Korea after crossing the military border with South Korea without permission, a US official has confirmed.

Two US officials said the soldier detained was Private 2nd Class Travis King, 23, who had just been released from a South Korean prison where he’d been held on assault charges and was facing additional military disciplinary actions in the United States.

At a briefing, Defence Secretary Lloyd Austin confirmed the crossing was deliberate and that he was concerned at the situation.

Mr Austin said: “One of our service members who was on a tour wilfully and without authorisation crossed the demarcation line. He is in custody.

“We are closely monitoring the situation and working to notify the soldier’s next of kin. I’m absolutely foremost concerned about the welfare of our troop.”

A defence official told CNN there was no indication the soldier was planning to defect and he was not escorted to the airport because he was no longer in custody.

His flight, ABC News reported, was bound for Fort Bliss, Texas.

An official also told CBS News the alleged defector managed to join the border tour after somehow managing to return through airport security.

A witness told the broadcaster that the man in question ran away from the tour laughing as he did so

“This man gives out a loud ‘ha ha ha,’ and just runs in between some buildings,” they said.

South Korean news site Daejon Ilbo added North Korea is trying to recruit King.

North Korea’s Panmon Hall (rear C) and the military demarcation line separating North and South Korea, at the Joint Security Area of the Demilitarized Zone
(
AFP via Getty Images)

The Military Demarcation Line (MDL) marks the border between North and South Korea. Sometimes known as the ‘Armistice Line’, it is surrounded by a demilitarised zone and is one of the most heavily fortified areas in the world.

In a statement, the United Nations Command said: “A US National on a JSA orientation tour crossed, without authorisation, the Military Demarcation Line into the Democratic People’s Republic of Korea (DPRK).

“We believe he is currently in DPRK custody and are working with our KPA counterparts to resolve this incident.”

South Korean Travel Planning said tours to the Joint Security Area (JSA) have recently resumed. Bloodshed and gunfire have occasionally occurred there, but it has also been a venue for numerous talks and a popular tourist spot.

The US has imposed a travel ban on its citizens to North Korea “due to the continuing serious risk of arrest and long term detention of US nationals.”

North Korea’s tyrannical leader Kim Jong Un walks with then US President Donald Trump north of the Military Demarcation Line in 2019
(
AFP/Getty Images)

The individual concerned was on a tour of the Korean border village of Panmunjom.

The Mirror has contacted US officials from the Department of Defence for comment.

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.

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 U.S. sent high-profile missions to secure their freedom.

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.

The most famous incident at Panmunjom happened in August 1976, when two American army officers were killed by ax-wielding North Korean soldiers. The U.S. officers had been sent out to trim a 40-foot (12-meter) tree that obstructed the view from a checkpoint. The attack prompted Washington to fly nuclear-capable B-52 bombers toward the DMZ to intimidate North Korea.

In 2016, American college student Otto Warmbier was detained at Pyongyang International Airport.

The demilitarised zone divides North and South Korea
(
Getty Images AsiaPac)

Warmbier was left in a vegetative state after North Korea claimed he had stolen a propaganda poster and sentenced him to 15 years of hard labour.

He was flown home and died shortly after aged 22.

The rogue state denies accusations it tortured Warmbier and says it is the main victim in the incident.

A federal judge ruled Warmbier’s family should receive $240,300 from a North Korean bank account.

South Korean soldiers prepare barriers on Tongil bridge as they wait for the convoy carrying South Korean president Moon Jae-in, leading to the Demilitarized Zone, in 2018
(
AFP/Getty Images)

The MDL, meanwhile, was put in place at the end of the Korean War in 1953 and it is around 148.5 miles long. The demilitarised zone stretches to two kilometres on either side.

The area is filled with mines and is considered one of the world’s most fortified areas with armed guards on alert all hours, every day.

It comes amid heightened tensions between North Korea and the US as the latter deployed a nuclear-armed submarine to South Korea for the first time in over 40 years.

orean People’s Army soldiers stand beneath the entrance to a pavillion before the Military Demarcation Line
(
AFP via Getty Images)

South Korea’s Defence Ministry said the USS Kentucky arrived in the city of Busan today.

A bilateral consulting group of South Korean and US officials met on Tuesday in Seoul to discuss strengthening their nations’ deterrence capabilities against North Korea’s evolving nuclear threats.

South Korean soldiers stand guard in a guard post near the Demilitarized zone
(
AFP via Getty Images)

The Nuclear Consultative Group (NCG) was established as part of agreements Presidents Joe Biden and Yoon Suk Yeol made when they met in April.

President Biden said after the April summit: “Both sides affirmed that the NCG will play an integral role in discussing and advancing bilateral approaches, including guidelines, to nuclear and strategic planning and responses to (North Korean) aggression.”

North Korean leader Kim Jong Un has railed against the West and continues to pursue a policy of creating nuclear weapons.

The border is surrounded by a demilitarised zone
(
Getty Images)

His sister and senior adviser, Kim Yo Jong, warned that the US moves to reinforce its extended deterrence commitment to South Korea will only make North Korea “go farther away from the negotiating table desired.”

“(North Korea) is ready for resolutely countering any acts of violating its sovereignty and territorial integrity,” Kim Yo Jong said. “The US should stop its foolish act of provoking (North Korea) even by imperilling its security.