A former vice environment minister in charge of China's pollution controls has been expelled from the ruling Communist Party for corruption, its anti-graft watchdog said on Thursday, as smog warnings were issued across the country.

Zhang Lijun, 63, was placed under investigation in July for "suspected serious violation of the law and discipline", typically a reference to corruption.

The probe found that Zhang took advantage of his position to secure jobs for his relatives, sought business gains for companies in exchange for bribes and traded promotions for money, among other offences, the Central Commission for Discipline Inspection (CCDI) said in a statement.

Zhang, who retired from the ministry in 2013, was stripped of his party membership and transferred to judicial authorities -- normally a precursor to prosecution and trial, with conviction virtually guaranteed in the country's party-supervised courts -- according to the statement.

"Zhang Lijun was a high-ranking official of the party but he lost his ideals and belief and severely violated party discipline," it said, adding his actions were "vicious in nature and the circumstances were serious".

The announcement came as the National Meteorological Centre issued smog warnings for Thursday and Friday in at least 14 provinces and metropolises across the country, including Beijing and Shanghai.

Public anger has mounted in China over dire air pollution, which consistently sees levels of PM2.5 -- harmful microscopic particles that penetrate deep into the lungs -- far above the World Health Organization's recommended maximum, particularly in winter.

The pollutants mainly come from coal burning for electricity and heating, and vehicle emissions.

Zhang was in charge of pollution prevention and control at the ministry of environmental protection, the Beijing News reported previously.

It said whistle-blowers reported that three companies with close links to him made more than two billion yuan ($308 million) selling thousands of substandard exhaust emission detection devices to a government project after he influenced the bidding process.