North Korea says it has arrested a US university student for what it said was a "hostile act" orchestrated by the American government to undermine the nation.
State media said the University of Virginia student entered the country under the guise of a tourist and plotted to destroy North Korean unity with "the tacit connivance of the US government and under its manipulation".
The North's official Korean Central News Agency said in a short report that the student, whom it identified as Warmbier Otto Frederick, was "arrested while perpetrating a hostile act", but did not say when he was detained or the nature of the act.
Pyongyang sometimes list English-language surnames first, in the Korean style. The University of Virginia's online student directory lists someone named Otto Frederick Warmbier as an undergraduate commerce student.
A China-based tour company specialising in travel to North Korea, Young Pioneer Tours, confirmed that one of its customers, identified only as "Otto", had been detained in the North's capital, but provided no other details.
North Korea's announcement comes amid a diplomatic push by Washington, Seoul and their allies to slap Pyongyang with tough sanctions for its recent nuclear test. In the past, North Korea has occasionally announced the arrests of foreign nationals in times of tension with the outside world in an apparent attempt to wrest concessions or diplomatic manoeuvring room.
North Korea regularly accuses Washington and Seoul of sending "spies" to overthrow its government to enable the US-backed South Korean government to control the entire Korean peninsula. Some foreigners previously arrested have read statements of guilt that they later said were coerced.
Earlier this month, CNN reported that North Korea had detained another US citizen on suspicion of spying. It said a man identified as Kim Dong Chul was being held by Pyongyang and authorities had accused him of spying and stealing state secrets.
The US State Department said it could not confirm the CNN report. It declined to discuss the issue further or confirm whether the US was consulting Sweden, which handles US consular issues in North Korea because Washington and Pyongyang do not have diplomatic relations.
North Korea has previously released or deported US detainees after high-profile Americans visited the country.
The Korean peninsula remains in a technical state of war because the 1950-53 Korean War ended with an armistice, not a peace treaty. About 28,500 American troops are stationed in South Korea.
North Korea is holding at least three South Koreans and one Canadian.
Last month, North Korea's Supreme Court sentenced a Canadian pastor to life in prison with hard labour for what it called crimes against the state. The offences he was charged with included harming the dignity of the North's leadership and trying to use religion to destroy the system, according to the North's state media.