An American who crossed into North Korea "without authorization" was likely in custody in the secretive country, United Naitons officials said Tuesday.

"A U.S. National on a JSA orientation tour crossed, without authorization, the Military Demarcation Line into the Democratic People’s Republic of Korea," the United Nations Command said on Twitter. "We believe he is currently in DPRK custody and are working with our KPA counterparts to resolve this incident."

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