That's the claim that a former prisoner made to the London newspaper The Guardian. He said that prisoners were forced by prison guards to play games like World of Warcraft for hours on end, earning in-game currency, often by endlessly repeating mundane tasks. The guards would then take those earnings and sell them online for real money.

"Prison bosses made more money forcing inmates to play games than they do forcing people to do manual labour," Liu told the Guardian. "There were 300 prisoners forced to play games. We worked 12-hour shifts in the camp. I heard them say they could earn 5,000-6,000rmb [£470-570] a day. We didn't see any of the money. The computers were never turned off."

Liu said that if the prisoners failed to meet set quotas, they were severely beaten.

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