China has sent 12 inspection teams to regions worst hit by air pollution, as some 15 percent of the country will remain cloaked in smog until Thursday.

According to the Ministry of Environmental Protection on Sunday, the inspection teams have headed to Beijing, Tianjin, Hebei Province and their surrounding areas, to review the local government response to the pollution and their implementation of September's central government action plan.

They will inspect major polluting industries such as steel, coal chemicals, glass and cement and check construction sites.

Violations found by the inspection teams will be publicized.

Almost all provinces in central and east China have bee under a cloud since Friday, while Beijing and provinces of Hebei, Shanxi, Shandong, Henan and Liaoning reported "severe smog."

Beijing on Friday raised its alert to orange for the first time and advised schools and kindergartens to cancel outside sports classes. School will be closed and government vehicles taken off the road, if the alert is raised to red.

Meteorological officials said a weak cold spell on Feb. 24 might help lift the air quality in Beijing, but the smog will persist until the middle of the week.