SEOUL: North Korea announced Friday the arrest of a US university student for what it said were "hostile" acts orchestrated by the US government.

The University of Virginia student was accused of entering the country under the guise of a tourist and plotting to undermine North Korean unity with "the tacit connivance of the US government and under its manipulation," the North's official Korean Central News Agency reported. It didn't say when he was arrested.

KCNA identified the student as Warmbier Otto Frederick, saying he was under investigation. North Korea has sometimes listed 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 specializing in travel to North Korea, Young Pioneer Tours, confirmed that one of its customers had been detained in Pyongyang, the North's capital.

North Korea's announcement comes as it faces a diplomatic push by Washington, Seoul and their allies to slap the North with tough sanctions for its recent nuclear test. In the past, North Korea has occasionally announced the arrests of foreign detainees in times of tension with the outside world in an apparent attempt to wrest concessions or diplomatic maneuvering room.

North Korea has also claimed outside conspiracies in past announcements of such arrests. Those arrested have sometimes 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 the North and said authorities had accused him of engaging in 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 with Sweden, which handles US consular issues in North Korea because Washington and Pyongyang do not have diplomatic relations.

North Korea in the past has sometimes released or deported US detainees after high-profile Americans visited the country. Last year, North Korea released two American detainees after a secret mission to the North by James Clapper, the top US intelligence official. Critics say such trips have provided diplomatic credibility to the North.

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 other South Koreans and one Canadian.

Last month, North Korea's Supreme Court sentenced a Canadian pastor to life in prison with hard labor for what it called crimes against the state. The offenses he was charged with included harming the dignity of the North's leadership and trying to use religion to destroy the North Korean system, according to the North's state media.