Protesters Demand the Release of Labor Leaders

Thousands of demonstrators shouting for the release of detained labor leaders converged on government offices in China's industrial northeast, in a protest that authorities warned was illegal.

Participants in the demonstration in Liaoyang and a labor rights group said three protest leaders were detained Wednesday while seeking talks with city officials.

Another leader was detained Sunday near his home, the China Labor Bulletin said.

The protests are a warning sign of the problems China faces as it shuts down unprofitable state-owned factories.