North Korea confirmed Wednesday that it detained a U.S. citizen in April for committing what it described as "criminal acts of hostility" against the country.The state-run Korean Central News Agency identified the citizen as Kim Sang Dok, who was invited to Pyongyang University of Science and Technology to teach accounting as a professor.North Korea believes Kim, detained on April 22 at Pyongyang's international airport, was trying to "overturn" the country's system through his acts in the past and during the latest stay, KCNA said, without providing further details.The detention was announ…READ FULL ARTICLE