Mr. Kim’s predicament was not known until January 2016, when the North Korean government let CNN interview him in Pyongyang. At that time, Mr. Kim identified himself as a 62-year-old naturalized American citizen who lived in Fairfax, Va. He said he had once run a trading and hotel services company in Rason, a special economic zone near North Korea’s borders with China and Russia.
He said he had been arrested in October 2015 while meeting with a former North Korean soldier to receive classified data.
Tony Kim, also known as Kim Sang-duk, was arrested in April 2017. He had spent a month teaching accounting at Pyongyang University of Science and Technology, a Christian-funded college, and was trying to board a plane to leave the country when he was arrested, according to university officials.
Mr. Kim, who is in his 50s, studied accounting at the University of California, Riverside, and at Aurora University, and he worked as an accountant in the United States for more than a decade, according to his Facebook page.
Kim Hak-song was arrested on May 6, 2017. He volunteered at Pyongyang University of Science and Technology, doing agricultural development work at its research farm.
According to CNN, Mr. Kim, an ethnic Korean, was born in Jilin, China, near the North Korean border, and emigrated to the United States in the 1990s. After becoming an American citizen, the network said, Mr. Kim returned to China and studied agriculture in Yanbian before moving to Pyongyang.
“It’s also worth remembering that North Korea’s practice of seizing, imprisoning and, in one case, probably torturing Americans represents reprehensible behavior that says something about the nature of the regime,” said Evans J.R. Revere, a former State Department diplomat who specializes in East Asia. “I would not give Pyongyang too much credit for undoing something it shouldn’t have been doing in the first place.”