CUOMO: Right now a U.S. citizen is being detained by North Korea. He is the third American being held by that regime. And it's raising tensions even more as an American carrier strike group approaches the region. CNN's Ivan Watson live in Seoul, South Korea, with more. Ivan, what do we know?</s>IVAN WATSON, CNN CORRESPONDENT: OK, this is a professor by the name of Tony Kim, Chris. And he was -- had been teaching for several weeks at the Pyongyang University of Science and Technology. Now, he was on the way out of the country, leaving Saturday morning from Pyongyang International Airport, and that is when the North Koreans grabbed him. We do not know why and we don't know what kind of charges they may press against him. But once the North Koreans do this, judging by past behavior and trends, it is very, very serious. The other two Americans that are currently in custody are University of Virginia student named Otto Warmbier and another man named Kim Dong-chul. They were grabbed in 2015, 2016, and they face either 10 or 15 years of hard labor for various charges that the North Koreans have pressed against them.
American Detained in North Korea.