Two power plants operated by China Datang Group were found using high-sulphur coal that did not meet emission standards, the ministry branch said in a statement on Tuesday.

Datang's Baoding thermal plant burned 547,100 tonnes of coal in 2018 that failed to meet environmental standards, the ministry said. Its Qingyuan thermal power plant burned low-quality coal and more overall than the maximum allowed by the ministry in 2017 and 2018, it said.

The Hebei government will start formal legal investigation of the two power plants, it said.

Datang Group is one of China's largest utility companies.

(Reporting by Meng Meng and Dominique Patton; Editing by Tom Hogue)