SEOUL — North Korea has expanded its political prison camps in the past decade to hold about 200,000 people in "horrific" conditions, with some inmates eating rats to survive, Amnesty International said Wednesday.
A report from the London-based rights group painted a nightmarish picture of overwork, starvation and executions which detainees were forced to watch.
Amnesty said it had obtained satellite images revealing the location and size of the camps, along with new testimony from former inmates of the Yodok camp complex and others.
The ex-detainees testified that "prisoners are forced to work in conditions approaching slavery and are frequently subjected to torture and other cruel, inhumane and degrading treatment", Amnesty said.
All ex-detainees at Yodok in South Hamkyong province had witnessed public executions, it said.
Amnesty said comparison of the latest images with ones from 2001 showed a significant increase in the scale of the camps.
"As North Korea seems to be moving towards a new leader in Kim Jong-Un and a period of political instability, the big worry is that the prison camps appear to be growing in size," said its Asia-Pacific director Sam Zarifi.
Leader Kim Jong-Il is grooming his youngest son Jong-Un as eventual successor.
Amnesty said that in just one camp, Kwanliso 15 at Yodok, thousands are believed to be held after being judged "guilty by association" or simply because one of their relatives has been detained.
Many did not even know what crimes they were accused of.
Amnesty quoted Jeong Kyoungil, a detainee at Yodok from 2000-2003, as saying the working day started at 4am and ended at 8pm but was followed by two hours of ideological education.
"If we don't memorise the 10 codes of ethics, we would not be allowed to sleep," Jeong was quoted as saying in a Seoul interview last month.
Only those who finished their assigned tasks would receive the ration of a 200 gramme (seven ounce) bowlful of corn gruel, and inmates died daily.
"Seeing people die happened frequently -- every day," Jeong said.
"Frankly, unlike in a normal society, we would like it rather than feel sad because if you bring a dead body and bury it, you would be given another bowl of food."
Some prisoners ate rats or picked corn kernels out of animal excreta to survive, the report said. One former detainee at Yodok estimated that 40 per cent of inmates died from malnutrition between 1999 and 2001, it added.
Amnesty said authorities are also known to use a cube-shaped "torture cell" in which it is impossible either to stand or lie down.
The rights group said inmates deemed disruptive were thrown in for at least one week, "but Amnesty International is aware of one case of a child thrown into the cell for eight months".
Former detainees have frequently given similar accounts of harsh and life-threatening conditions in the camps. The US State Department in its 2010 human rights report cited estimates of 150,000-200,000 detainees.