What Happened to American POWs Kept Behind After the Korean War

U.S. Army PFC Ryeu Sup "Roy" Chung was reported AWOL on June 5, 1979 from his unit in Germany, Troop C, First Squadron, Second Armored Cavalry Regiment. Roy -- sometimes reported as Korean-American, but actually a Korean citizen who had been living in the U.S. -- was said to be devout Christian. A commander's report "revealed no evidence or indication of foul play, drug use or defection."
But PFC Chung later surfaced in North Korea, according to DPRK radio. North Korean officials at Panmunjom first refused to answer questions about Chung, then stated he had escaped to North Korea because he could not "stand the life in the aggressive imperialist U.S. Army."
While some Americans did defect to North Korea across the DMZ, they were generally celebrated in North Korean propaganda. Chung's family did not believe he defected and little, if anything, has been heard about him since.
A previously classified 1993 State Department document released to KPOWS (Nov '12) seem to concern this case (although the dates are slightly off and the subject is referred to as Chong In-Sik.) 
According to an informant, a Korean-American member of the  U.S. military defected in Germany in 1980, travelled through Czechoslovakia and Russia and arrived in North Korea in October 1980. He was then arrested and imprisoned in "a special prison reserved for sensitive prisoners," in a place called Song Heli (phn), some 50 kilometers NE of Pyongyang.
The man died on Jan. 1, 1986, after being beaten by guards.
KPOWS would like to determine if this information is indeed about PFC Chung and, if so, make sure his family has it. Pls email us if you can help: investigator@kpows.com
We also note that North Korean agents were kidnapping South Koreans and others in Europe and elsewhere around the world at that time, and that we have previously obtained an U.S. Army intelligence report (see below) that a North Korean commando captured in South Korea during 1962 reported one of his team's missions was to "kidnap US servicemen and return them" to North Korea. [The document also refers to a 4-man RoK team kidnapped in July '62.]
We have followed the Chung case for 20 years and found little evidence the U.S. government made substantial efforts to get to the bottom of the disappearance and recover the young soldier. This may be because he was written off as a defector and a Korean citizen -- and, of course, the usual lack of focus on American servicemen reported in North Korea.
You'll note the informant also gave the Embassy a list of people held at the special prison, including "Japanese and a number of ethnic-Korean Japanese who had gone to North Korea."

Americans Were Held at War's End

Reported Alive Years After

What Happened to Them?

Pentagon Study on American POWs in North Korea