China’s official news agency, Xinhua, reported the nine workers had been hired by businessman Han Fengguo, who allegedly had an underground passage dug beneath his coal retailing business in the Guye District of Tangshan.
The tunnel was connected to a state-owned coal mine and was used for illegal coal extraction.
The surface of the passage collapsed early on Wednesday during heavy rain, trapping the nine workers, according to a preliminary investigation.
Han has been detained by the police and a rescue operation is underway.
