US soldier detained by North Korea after crossing border

An American citizen crossed into North Korea on Tuesday and was taken into custody by the country's forces, international officials said. 

The United Nations Command, which operates the Joint Security Area demilitarized zone between North and South Korea, released a statement saying the man was on a tour of the area and "crossed, without authorization, the Military Demarcation Line into [North Korea]." The UN Command added that it was "working with our [North Korean] counterparts to resolve this incident."

American officials told CBS News that the man in question was a U.S. soldier, Private 2nd Class Travis King, who was reportedly being escorted back to the United States from South Korea for disciplinary reasons. After going through airport security, King allegedly returned and managed to join a border tour group before crossing into North Korea willingly, officials told CBS. 

Tours of the Joint Security Area are commonplace, and "tourists can visit the area from South Korea while unarmed soldiers trail closely behind," The New York Times noted, so it is unclear how King was able to cross the border. While both North and South Korean soldiers on each side of the Joint Security Area are unarmed, neither are allowed to cross into the other's territory. 

King becomes the first known American to be taken captive in North Korea since Bruce Byron Lowrance​ illegally entered the country from China in 2018, and ended up being detained for a month. The most high-profile American captive of North Korea was likely Otto Warmbier, who was arrested in Pyongyang in 2016 and accused of stealing a propaganda poster. He was held in North Korea for 17 months before being flown back to the United States in a coma, where he died days later. 

Tuesday's incident occurred as relations between the U.S. and North Korea continue to sour.