Beijing authorities have issued a second pollution "red alert", little more than a week after its first ever such warning, SIA reports citing the BBC.
The Chinese capital will endure dense smog from Saturday until Tuesday, the Beijing Meteorological Service said.
The National Meteorological Centre said a wide area from Xian in central China to Harbin in the north-east would also be affected.
The alert triggers restrictions on vehicle use, factories and building.
The government has promised to crack down on often hazardous levels of pollution around the country.