Police in Heilongjiang rescued more than 30 mentally and intellectually handicapped workers enslaved at a construction site in the Hulan district economic development zone last week, according to Life newspaper.
The 33 men were locked in a 30 sq metre room when officers forced their way into an apartment building in Harbin's Chang-qing street on March 13.
They slept on straw mats and were fed rice porridge, preserved vegetables and restaurant leftovers, an officer said. There were no toilets or places to wash.
Some of the slaves had been forced to carry bricks and sand at a construction site for three years and those who tried to escape had been beaten, the report said.
The raid was launched after two police academy students discovered the body of one of the workers who had leaped from the building that day. He had been beaten.
The men have accents from all over China but most were lured from Harbin's main train station.