Kenneth Bae has been detained by North Korea since this past November on charges that he tried to overthrow the government. This is a crime that could possibly yield a death sentence. The exact reason why he was arrested hasn't been officially confirmed, however his detainment appears to be over photos he took while in the country.
News sources have conflicting reports but they all seem to agree that he is being held because of images he took of orphans begging for food in markets. The US State Department has said it's working on the case. A Korean news agency claims says Bae has “admitted that he committed crimes aimed to topple the DPRK (The Democratic People's Republic of Korea).”