PYONGYANG, North Korea. — Multiple reports out of the Korean Peninsula indicate that the North has detained another U.S. citizen, which, if confirmed would be the third citizen they detained.

Tony Kim, who had been a professor at the Pyongyang University of Science and Technology, was detained by North Korean officials while in the airport, according to the Swedish Embassy, which handles consular matters for the US in North Korea.

The incident comes in the midst of a war of words between the North and the United States, and fears that it could lead to a military conflict.

The charges weren’t officially known early Sunday.