An estimated 200,000 people are held as prisoners in North Korea's network of political prison camps, according to the latest report by Amnesty International.
According to former detainees at the political prison camp at Yodok, prisoners are forced to work in conditions similar to slavery and are frequently subjected to torture and other cruel, inhumane, and degrading treatment. All the detainees at Yodok have witnessed public executions, the report said.
The images reveal the location, size and conditions inside the camps.
North Korea can no longer deny the undeniable. For decades the authorities have refused to admit to the existence of mass political prison camps, said Sam Zarifi, Amnesty International Asia Pacific Director.
These are places out of sight of the rest of the world, where almost the entire range of human rights protections that international law has tried to set up for last 60 years are ignored.
Amnesty International believes the camps have been in operation since the 1950s, yet only three people are ever known to have escaped Total Control Zones and managed to leave North Korea.
According to the testimony of a former detainee at the revolutionary zone in the political prison camp at Yodok, an estimated 40 per cent of inmates died from malnutrition between 1999 and 2001, the report added.