North Korea is expanding its main political prison camps, a human rights group has warned, publishing satellite images that show more guard posts, increased construction and developing agricultural areas.
Prisoners can be interned for years in the secluded mountain camps, where conditions are dire. In the freezing climate, some inmates die of frostbite, while public executions, torture and death by starvation are common, according to a report by Amnesty International in 2011.
Satellite images of the gulags from the Committee for Human Rights in North Korea (HRNK) and DigitalGlobe, a commercial earth image provider, have led researchers to conclude that the nation is either increasing its number of political prisoners or consolidating its labour camps.
Since 2009, the notorious Camp 25, also known as Kwan-li-so no. 25 and Susong Correctional Centre, on the northeast coast of North Korea, has grown by 72%.
Reasons for the expansion may include increased efforts to stem the flow of defectors before Kim Jong Il died so that the former ruler could ensure his son Kim Jong Un could take power, the HRNK said.
It also suggested Kim Jong-un may have pioneered a further crackdown on dissidents after he assumed power, or was consolidating its camp system
The human rights group warned that if some camps were being shut down it was vital that any evidence of abuses was not destroyed, or the remaining prisoners simply executed.
See more images of expansion over the last 10 years below