Transcript for Another American detained in North Korea

Next tonight new provocations from North Korea detain an American as he was leaving following a one month university teaching assignment there. And tonight North Korea threatening to sink a US aircraft carrier heading their way ABC's Bob Woodruff is in Seoul South Korea tonight. Yeah tonight in America. Accounting professor detained in North Korea the latest example of rising tensions the private North Korean university where Tony Kim had been teaching for several weeks. Tells ABC news the 58 year old was taken into custody Saturday at the Pyongyang airport. As it was trying to leave the country with his wife Kim's detention brings the total number of Americans held in North Korea to at least three. Hey man don't Morris mistake of my eye. Including 22 year old QBA student auto warm beer now a prisoner of more than a year. The north Koreans say this security video shows him stealing a political banner from the hotel. Where he was staying with a tour group warm beer was sentenced to fifteen years hard labor last year. You didn't vote. He didn't like. The third American businessman Kim Dong two serving a ten year sentence whenever tensions with the US. Get stronger they heightened. They take steps like this as bargaining chips. The these are three American bargaining chips that they now have this as the rhetoric continues to escalate. North Korea quoted this weekend as saying it's ready to sink the USS Vinson aircraft carrier expected to arrive in the region in the next few days. At a complicate this on Tuesday North Korea will be celebrating its 85 anniversary of their people's army. Now in the past they've used these kinds of celebrations to flex their muscles. So it's always possible Kim Jong I could use it to launch another nuclear test Tom the world will be watching for any other provocations are right Bob thanks.

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