Shin Dong-hyuk poses in Paris on May 2, 2012, before a news conference to present the book "Escape from Camp 14" by former Washington Post journalist Blaine Harden. (Jacky Naegelen/Reuters)

Shin Dong-hyuk, the North Korean prison camp survivor who has admitted that parts of his well-known tale are inaccurate, has urged his supporters to continue publicizing the “horrendous and unspeakable horrors that are taking place” in the totalitarian state.

As he prepares for new efforts by Kim Jong Un’s regime to discredit his testimony, Shin has said he “may or may not be able to continue in my work and efforts in trying to eliminate the political prison camps and bring justice to the oppressed.”

Shin, the only person known to have escaped from one of North Korea’s total-control zones, was the subject of the best-selling book “Escape From Camp 14,” written by former Washington Post journalist Blaine Harden, and has become the most prominent critic of North Korea’s human rights record.

His testimony of torture and imprisonment played a large role at the U.N. commission of inquiry into North Korea’s human rights abuses, which triggered the most concerted push yet to hold the state’s leaders accountable for decades of violations.

But Shin has now admitted that many of the places and timing of events in his telling of his story were wrong, although he insists the horrific treatment he has described so many times did happen.

“We all have something in the past that we never want brought to light,” Shin wrote on his Facebook page Sunday. “I too, forever wanted to conceal and hide part of my past. We tell ourselves that it’s okay to not reveal every little detail, and that it might not matter if certain parts aren’t clarified.”

Shin is traveling outside South Korea and has not answered requests for comments, although he is in touch with his wife and supporters, who say he is “very emotional” about the situation.

“Nevertheless this particular past of mine that I so badly wanted to cover up can no longer be hidden, nor do I want it to be,” he wrote, apologizing for the inaccuracies in his telling of his story.

Saying that his credibility might have been too damaged to continue his work, he urged his supporters to continue their fight against the North Korean regime. “But instead of me, you all can still fight,” he wrote. “The world still needs to know of the horrendous and unspeakable horrors that are taking place.”

Shin was forced to acknowledge the problems with his story after other defectors in South Korea began questioning his version of events and threatened to expose him.

In “Escape From Camp 14” and in his testimony to the U.N. commission, Shin has said he was born and spent his life in Camp 14, a sprawling high-security political prison in the mountains north of Pyongyang, until his escape in 2005.

But Shin admitted to Harden on Friday that when he was about 6, he, his mother and his brother were transferred to another prison camp, Camp 18, across the Taedong River from Camp 14.

In Camp 18, he learned that his mother and brother were plotting to escape and betrayed them to the prison guards, directly leading to their executions at that prison, not in Camp 14 as he had previously stated.

Shin also now says that he escaped from the camps on two occasions, in 1999 and 2001. Much of the worst torture he describes in the book as happening when he was 13, when guards suspected him of plotting to escape, actually happened when he was 20 and repatriated after escaping to China.

North Korea has already tried to undermine Shin’s testimony and is certain to seize on these admissions to try to discredit him.

Human rights activists said that this could significantly set back the international campaign to indict Kim and his cronies for crimes against humanity.

Shin has been the most high-profile of defectors agitating for change in North Korea. In September, he was honored by Human Rights Watch for his “tireless efforts to expose and end atrocities in North Korea,” and more recently, he was featured in “Light Through the Darkness,” a report from the Bush Institute, part of the George W. Bush Presidential Center.