The U.S. confirmed Tuesday that one of its service members was taken into custody in North Korea after crossing the militarized border while on a tour.
The soldier, who has not been publicly identified, "willfully and without authorization crossed the military demarcation line," Defense Secretary Lloyd Austin told reporters at the Pentagon.
Austin said the U.S. military believes the individual is in North Korea's custody.
"We're closely monitoring and investigating the situation and working to notify the soldier's next of kin, and engaging to address this incident," he said. "I'm absolutely foremost concerned about the welfare of our troop. And so we will remain focused on this, and again, this will develop in the next several days and hours. We'll keep you posted."
Multiple media reports identified the individual as Pvt. Travis King. He was reportedly being escorted back to the U.S. to face disciplinary action after being held in military detention in South Korea.
King had cleared airport security in South Korea on his way back to the U.S. when he joined a tour group that was slated to visit the border village of Panmunjom where he crossed into North Korea illegally, according to media reports.
Panmunjom, which is known as the "truce village," is a popular tourist destination. It lies within the demilitarized zone between the North and South, and has been repeatedly used as a venue for peace talks, including an inter-Korean and U.S. summit in 2019 in which ex-President Donald Trump made a landmark visit.
A person who was touring Panmunjom alongside King told CBS News that he was touring one of the buildings when "this man gives out a loud 'ha ha ha,' and just runs in between some buildings."
The incident prompted a flurry of military activity.
"I thought it was a bad joke at first, but when he didn't come back, I realized it wasn't a joke, and then everybody reacted and things got crazy," the witness, who was not identified, told CBS News.
