North Korea appears to be still operating one of its largest political prison camps, contrary to media reports that it might have been shuttered, a major human rights group here said based on satellite imagery of the site.

The Committee for Human Rights in North Korea (HRNK) issued a report, in partnership with DigitalGlobe, on the reclusive communist nation's notorious gulags.

Multiple photos, taken from November 2010 to October 2012, show buildings and activity in Camp 22 in the northeastern county of Hoeryong.

The imagery "does not support reports that Camp 22 was shut down or abandoned during 2012," the report said. "Harvesting of crops continues as does coal production, making it not yet clear that the camp has closed."

The level of activity and the state of the agricultural, industrial and civil infrastructure in the area suggests that the camp remains operational, it added.

The committee, established in 2001, has stepped up efforts to publicize the brutality of North Korea's concentration camps, where tens of thousands of people are believed to be held.

In the report, it recommended "immediate access to the prison camps by the International Committee of the Red Cross (ICRC) and the World Food Program."

It also called for the creation of an international commission of inquiry to investigate North Korea's breaches of international human rights and criminal laws.

"The North Korean regime's hiding and distorting the harsh reality of North Korea's unforgiving political prison camp system is no longer an option," said Greg Scarlatoiu, executive director of the HRNK. "With constant satellite imagery, we can maintain a watch over these camps even if no outside entry is allowed." (Yonhap News)