Here is an eyewitness account from a former North Korean prison guard. His name is Ahn Myong Chol and he served in the Hoeryong concentration camp, among other places. He and his story are described by David Hawk in online materials free to all.
Ahn, born in 1969 into a “good” (Party member) family in Hangwon, did his compulsory military service in four consecutive prisons between 1978 and 1994. His last assignment was Hoeryong, the only one of the four that is still operational.
Ahn’s father was a good man in other ways. In fact, he was caught doing a good thing. He gave food to one of his neighbors without authorization. This is reactionary and subversive by NK government standards. Knowing that his father was facing problems and therefore the whole family would be drawn into them, Ahn took his wife across the Tumen to China. He eventually made it to Seoul, where he began to tell his story. This became a book, and even testimony before the United States Congress.
Back in 2002, when technology allowed us to see certain truths about Hoeryong via satellite, Ahn was there to identify what we were seeing. We now know the location and purpose of each building in the prison complex. Ahn was able to be so familiar with these things due to his position as a truck driver.
Ahn confirms the shock one experiences upon first arriving at the camp. Walking skeletons. In years. Cripples in rags. It doesn’t get better with time. He knew that up to 2,000 people died in the camp from malnutrition each year. Most of these were children. Perhaps ten executions a year, of people who had been caught eating the food of the harvest. More deaths, by beatings, of prisoners who had not been meeting production quotas.
The only meat that people ate was from captured rats, snakes, and frogs.
Marriage almost totally prohibited.
A pregnant woman was executed because of her pregnancy.
I do not mean to “smear” North Korea or its government. The stories I tell come from credible eyewitnesses whose books are widely published. The idea is compassion. And a lot of praying. God can tell you more than you can do, but I think this is a good start.