An American student has been arrested in North Korea.

The arrest is the latest in a series of arrests of U.S. citizens.

Analysts say North Korea uses the citizens as bargaining chips.

The student is Otto Frederick Warmbier, 21, of Cincinnati, Ohio.

He is studying economics at the University of Virginia.

He "was caught committing a hostile act against the state," the official North Korean news agency, KCNA, reported on Friday.

Warmbier's actions were "tolerated and manipulated by the U.S. government," according to the dispatch.

Daniel Pinkston is a professor at Troy University in Seoul. He told VOA that:

"We can only speculate why he has been detained. But it is quite risky to visit (North Korea) as a tourist given the sensitivities regarding anything about the state, the leadership, government, and political system, or geo-politics in general."

Warmbier was a member of a trip organized by China-based Young Pioneer Tours. He was detained January 2, four days before North Korea conducted its fourth nuclear test in defiance of United Nation sanctions.

The United States and North Korea have no diplomatic relations. The U.S. State Department has, for years, issued strong recommendations and travel warnings against visiting North Korea because of the risk of arrest and longterm detention.

Many of the North Americans arrested by North Korea in recent years have had links to Christian Evangelical groups.

But Warmbier's social media accounts show no religious connections.

Approximately 200,000 North Koreans are believed to be in prison for their political views or religious beliefs, according to human rights groups.

I'm Mario Ritter.

Steve Herman reported this news for VOA News. Kathleen Struck adapted it for Learning English.