They were gradually released under a series of amnesties between 1953 and 1956 .
Between 1946 and 1950 , many of the Japanese POWs in Soviet captivity were released ; those remaining after 1950 were mainly those convicted of various crimes .
many were gradually released under a series of amnesties between 1953 and 1956 .
Between 1946 and 1950 , many of the Japanese POWs in Soviet captivity were released ; those remaining after 1950 were mainly those convicted of various crimes .