Updated

North Korea has confirmed the detention of an American citizen for alleged acts of hostility aimed at overthrowing the country.

The Korean Central News Agency says officials "intercepted" Kim Sang Dok at Pyongyang International Airport on April 22.

Wednesday's KCNA dispatch says authorities were detaining Kim and are conducting a detailed investigation into his alleged crime.

It says Kim was invited to Pyongyang University of Science and Technology to teach accounting as a professor.

The school's chancellor and the Swedish Embassy in Pyongyang earlier gave the information about Kim's detention but the reason for his arrest wasn't known. They used a different spelling of Kim's name.

The North is currently holding at least two other Americans, Kim Dong Chul and Otto Warmbier.