North Korean camps for political prisoners are expanding in size, according to a report from Amnesty International.

Citing new satellite images, the London-based human rights organization believes there are currently about 200,000 people in North Korea prison camps (out of a total population of about 25-million),

Amnesty released satellite photos which showed four of the six prison camps believed to exist in North Korea’s South Pyongyang, South Hamkyung and North Hamkyung provinces.

North Korea can no longer deny the undeniable, Sam Zarifi, Amnesty International’s Asia Pacific director, said in a statement.

Hundreds of thousands of people exist with virtually no rights, treated essentially as slaves, in some of the worst circumstances we’ve documented in the last 50 years.”

The prisons are notorious for forced starvation, torture and executions.

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, Zarifi said.

Amnesty explained that North Korea prison camps have been operating since the 1950s and can be divided into two types: “total control zones” where inmates are detained forever without any proper trials; and “revolutionary zones” where conditions are more lenient.

Amnesty has urged the North Korea government to close down the prison camps and release political prisoners.

Zarifi added: Most of the camps are called total control zones and the people who are there are kept there for life, almost always without any proper trials. Frequently family members are incarcerated, detained simply because somebody else in the family did something offensive, so we know very little about the camps.

He also declared: Conditions in these camps are inhuman and [leader] Kim Jong-il must close them immediately, he added.

A former prisoner, Kyoung-il Jeong, who spent three years in the notorious Yodok prison camp, told western media: The main reason for the deaths [in the prisons] was malnutrition. With such poorly prepared food people couldn't stand the harsh labor and died.

Kyoung-il Jeong testified that prisoners were fed 200 grams of corn gruel per daily and were often tossed into a cube-shaped torture cell where it was impossible to either stand or lie down.

Those caught trying to escape were often executed.

Seeing people die happened frequently – every day. Jeong said. When an officer told me to, I gathered some people and buried the bodies. After receiving extra food for the job, we felt glad rather than feeling sad.

Based on testimony by other Yodok detainees, Amnesty estimates that 40 per cent of prisoners died from hunger between 1999 and 2001.