North Korea on Wednesday confirmed that it was holding an American citizen, saying the man was being held for committing "hostile criminal acts with an aim to subvert the country".
The despatch by the North's official Korean Central News Agency, or KCNA, was its first official confirmation of the arrest in late April of Kim Sang-duk, who also goes by his American name, Tony Kim.
Law enforcement officials were investigating Kim's crime, KCNA said. It gave no further details.
Kim was detained at the airport in Pyongyang on April 22 while he was trying to leave the country. His arrest raised the number of Americans thought to be held by the secretive nation to three, the New York Times reported.
Kim had taught accounting at Yanbian University of Science and Technology in China before travelling to Pyongyang, where he taught for about a month at a sister school, the Pyongyang University of Science and Technology, according to Park Chan-mo, the university's chancellor.
The detention comes at a time of escalating tension on the Korean peninsula due to repeated weapons tests carried out by the Pyongyang regime and a verbal spat with the US, which has hinted at possible pre-emptive strikes.
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The South Korean news agency Yonhap said Kim was also engaged in humanitarian work in the North, helping orphanages in the country's northeast.
Last year, North Korea sentenced an American college student, Otto F. Warmbier, to 15 years' hard labour after accusing him of trying to steal a political banner from a hotel in Pyongyang.
It later sentenced another American, Kim Dong-chul, to 10 years' hard labour on charges of spying and other offences.
--IANS
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