N. Korea's 'gulags' in the frame

Amnesty released on Thursday satellite imagery of two camps where it claims physical and mental abuse of political prisoners is routine.

The organization used satellite imagery in their study of Kwanliso (Camp) 15 and Kwanliso 16.

Amnesty claimed that the latter appeared to have expanded in population size, given an increase in the number of structures though to be housing units. Operations at Kwanliso 15 appeared to be continuing, it said, although the population may have declined.

"Based on the satellite imagery analysis of Kwanliso 15 and 16, the political prison camps seem to be active and infrastructure maintenance on-going," said the report's conclusion.

Executions, torture

"The analysis demonstrates a possible increase in the population in Kwanliso 16, a population that is subjected to grave human rights violations including torture, executions, forced labour and horrific living."

The images detail significant economic activity such as mining and logging, which were carried out by a prison labor force, according to witness statements included in the report.

In addition to prisoners working long hours in dangerous conditions, it said, they were also subjected to denial of food as a form of punishment.

Murder, rape and torture

Details of extreme abuses were also included in the report's backgrounder, which carried testimony from a former prison camp guard, as well as former inmates.

The guard, named only as Mr. Lee, said he had seen prisoners forced to dig their own graves before being killed with hammer blows to the head.

Other inmates, he said, were beaten to death with sticks. Mr. Lee also recounted that several women had disappeared after being raped by officials, concluding that they had been secretly executed.

Large areas

The study noted the size of the camps, with Kwalinso 16 covering an area of 560 square kilometers (216 square miles) and Kwalinso 15 covering 370 square kilometers. Tight controls appeared to exist, it said, with a proliferation of guard towers and internal checkpoints.

In its conclusion, Amnesty urged the North Korean government to acknowledge the existence of the camps, something Pyongyang currently denies.

Amnesty also called for their immediate closure and the release of all prisoners of conscience and those held on the basis of "guilt by association."