North Korea’s government is pocketing billions of dollars by forcing its citizens to work in slave-like conditions in other countries, reports on October 29 said.

The workers are forced to labor for up to 20 hours a day in some cases—often under total surveillance and with very little food. Most of the workers receive no pay. In the cases when a worker does receive compensation, it is only a few cents for every dollar given to the North Korean government.

The government forces tens of thousands of its citizens to work abroad in this program, and the numbers are increasing. China and Russia hire the majority of the slave laborers, but some Middle Eastern nations are also capitalizing on the cheap labor.

The North Koreans normally work three to 10 years before returning home. And the government takes drastic measures to prevent them from being assimilated into the culture of the country they are working in. Vice News journalist Shane Smith traveled to Russia to see some of the labor camps and said they are designed to preserve the North Korean culture. “They outsource the labor into miniature North Korean villages, so you don’t ever lose the North Korean experience,” he said. “So it’s like North Korean-type buildings, North Korean propaganda. North Korean pictures, North Korean songs. They wake up and sing the North Korean anthem.”

Immediately upon returning to North Korea, the workers spend a month in reintegration camps. There they can catch up on any propaganda they missed out on while abroad.

North Korea is also careful to choose only family men to send abroad. They are usually over 40 years old and have children. Since the workers have family back at home, they know that if they try to escape, their loved ones will be brutally punished or killed.

The government of “supreme leader” Kim Jong-un is believed to be raking in between $1.2 and $2.3 billion per year from the practice.

How has the dangerous personality cult that rules over North Korea survived in the modern world for so long? How has such a spiteful, sadistic and emotionally unstable regime been allowed to develop and maintain nuclear weapons? How has a government that proudly commits crimes against humanity—torturing and enslaving tens of thousands—maintained its power for so many years?

The answer to all of those questions is China and, to a lesser degree, Russia. China and Russia are keeping the dangerous Kim regime afloat, and thereby prolonging the suffering of millions of North Korean people and imperiling global stability. To understand why, read Trumpet columnist Brad Macdonald’s article “Why China Supports North Korea.”