From 1967 until into the 2000's there is an unbroken chain of evidence that North Korean prisoners are tortured. Here is a short list of eyewitness proof:

• Detainee beaten unconscious for hunger-related rule infractions. 1997. Chongjin City.
• Detainees beaten with shovels if they did not work fast enough. Chongjin City.
• Detainees regularly placed in undersized punishment boxes for 15 days, unable to stand up or lie down. Danchun.
• Prisoner subjected to motionless kneeling and water torture, facial and shin beatings with rifle butts, leaving permanent damage to ear and eye. Pyongyang. 1994.
• Separate punishment cells from which few returned alive. Yodok.
• Prisoners beaten to death by work-unit leaders. Danchun. Late 80's.
• Former guard reports that in Hoeryong Camp there were so many beatings from guards that they were finally reprimanded.
• Male prisoners beaten by guards. Chongjin. Mid-2000.
• Detainees compelled to beat each other. Onsong.
• Detainee reports that his fingers were broken, he was kicked and beaten on head and face until ears, eyes, nose, and mouth were bleeding. 1997. Onsong.
• Out of 6 persons in adjoining cell (Pyongyang, 1997), prisoner says 2 were carried out on stretchers, 2 needed guard assistance to walk, only 2 could walk by themselves. Prisoners ordered to be motionless who moved, were handcuffed from the upper bars of their cells with their feet off the floor. Detainees who talked when silence was commanded were ordered to slap and hit each other...

The list goes on and on, but I will stop. Go to http://www.hrnk.org/ for more, including the "ethnic infanticide" victims.