From BBC News:
The men were said to have been discovered in a filthy 30sq m (320sq ft) room in Hulan, a city in the north-eastern province of Heilongjiang.
At least three people were detained, suspected of keeping the slaves.
College students reportedly saw a man jump to his death from a seventh-floor window, and raised the alarm.
Read also Dozens of slave workers freed in China: report from Reuters.