North Korea's official Korean Central News Agency said that Kim Hak Song had worked for the Pyongyang University of Science and Technology before he was held on Saturday.
While details remain sparse, North Korean state media added that "a relevant institution is now conducting detailed investigation into his crimes".
The KCNA report didn't say whether the two cases are connected.
North Korea tested two ballistic missiles in recent weeks, both of which flubbed. Kim taught accounting at the university for about a month.
It has carried out a series of missile launches this year and President Donald Trump has said military action against the rogue state has not been ruled out.
The regime described Kim Hak-song as "a man who was doing business in relation to the operation of Pyongyang University of Science and Technology". The agency declined to comment further, citing privacy considerations.
North Korea has arrested and jailed several USA citizens in the past decade, often releasing them only after high-profile visits by current or former United States officials or former U.S. presidents.
With his detention, Kim Hak Song becomes the fourth American citizen to be held in custody by the North Korean government.
Morning links: Blues need Game 2 repeat or better
By the 12:00 mark of the first period, it was already a three-goal lead with Jakob Silfverberg and captain Ryan Getzlaf tallying. The only shot that got past Nashville goaltender Pekka Rinne was an artful deflection by Alexander Steen in the second period.
A United States citizen has been detained by North Korea as tension mounts between Pyongyang and Washington.
North Korea on Friday accused the US and South Korean spy agencies of an unsuccessful assassination attempt on leader Kim Jong Un involving biochemical weapons. The U.S. also recently directed an aircraft carrier strike group toward the Korean Peninsula.
The 55-year-old former professor at Yanbian University of Science and Technology in China had reportedly been working on humanitarian projects in North Korea.
Two more U.S. citizens, Kim Dong-Chul and Otto Warmbier, were sentenced last year to 10 years and 15 years hard labour respectively.
Two months later, Kim Dong Chul was sentenced to 10 years hard labour for subversion.
In the midst of all the back and forth, Trump last week expressed a willingness to meet with Kim Jong-Un.
The arrests of two Americans in such a short span of time comes as Pyongyang exchanges hostile rhetoric with the USA over its banned missile and nuclear weapons programmes.
Comments