Update at 1010 hours KST on Monday: this article has been amended to include a statement from PUST.
North Korean authorities detained a U.S. citizen by the name of Kim Hak-song on Saturday, according to reports by the state-run news agency KCNA on Sunday.
The arrest of Kim, who was reportedly detained on suspicion of committing “hostile acts” against the country, brings the number of U.S. citizens held as prisoners in North Korea to four.
Mr. Kim is reported to be linked to the Pyongyang University of Science and Technology (PUST).
“A relevant institution of the DPRK detained American citizen Kim Hak Song on May 6 under a law of the DPRK on a charge of his hostile acts against it,” KCNA reported. “[Kim] had ran business at the Pyongyang University of Science and Technology (PUST).”
“A relevant institution is now conducting a detailed investigation into his crimes.”
In a statement on Monday, PUST said that Kim, known as Jin Xuesong in Chinese, was detained as he was about to leave the country after a stay of several weeks.
“During that visit, Mr Kim was at PUST to do agricultural development work with PUST’s experimental farm,” the statement reads. “We understand that this detention is related to an investigation into matters that are not connected in any way with the work of PUST. Therefore, we cannot comment on anything that Mr Haksong Kim is alleged to have done.”
“Life on campus and the teaching at PUST is continuing as normal for the Spring semester.”
The arrest came just two weeks after the detention of another U.S. citizen linked to PUST, Kim Sang-duk, also known as Tony Kim, at Pyongyang Airport on April 22.
Tony Kim taught in the Business Administration Department of both Yanbian University of Science and Technology, in northeast China and at PUST.
Last week North Korean authorities broke their silence on Kim’s detention, accusing him of “committing criminal acts of hostility” against the country’s government.
Norma H. Nichols, PUST’s Director of International Academic Affairs, told NK News after his detention that Kim had been “actively involved with humanitarian aid and relief,” both inside and outside the DPRK, but did not know why he had been detained.
“We understand that this detention is related to an investigation into matters that are not connected in any way with the work of PUST,” the University said in an official statement on his detention.
In addition to Tony Kim, two other U.S. citizens are in detention in North Korea: 22-year-old Otto Warmbier and 62-year-old Kim Dong-chul, both of whom are serving sentences of hard labor of 15 and 10 years respectively.
Warmbier was detained and sentenced for attempting to steal a poster from a room in the Yanggakdo Hotel in Pyongyang in January last year. Kim was sentenced in October 2015 for espionage.
At the time of publication the U.S. State Department had not yet responded to requests for comment.