North Korea has confirmed the detention of another American citizen for alleged acts aimed at overthrowing the country.
Kim Sang Dok, 58, an accounting instructor at Pyongyang University of Science and Technology, was "intercepted" at Pyongyang International Airport on April 22, according to the Korean Central News Agency.
It said he was being detained while authorities investigated his alleged crime.
Kim is the third American being detained in North Korea.
The other detainees are Otto Warmbier, who is serving a 15-year prison term with hard labour for alleged anti-state acts, and Kim Dong Chul, who is serving a 10-year term with hard labour for alleged espionage.
A university spokesman said Kim was trying to leave with his wife on a flight to China when he was detained.
The US State Department said it was aware of the report about a citizen being detained but declined further comment "due to privacy considerations".
Analysts say North Korea often attempts to use foreign detainees to wrest outside concessions.
Animosity between Pyongyang and Washington has spiked in recent weeks amid brinkmanship between North Korean leader Kim Jong Un and US President Donald Trump.
