Twelve teams will inspect factories, including those producing steel, coal, glass and cement, in Beijing, nearby Tianjin city and neighboring Hebei province, as well as their surrounding areas, the ministry said. The teams will review the local governments' responses to the bad air over the past few days, it said, adding that any violations found would be publicized.

The government is eager to bring about a visible improvement in China's bad air, which has caused discontent among its citizens and tarnished the country's image abroad.

While heavily polluting industries have emissions standards, they are not necessarily enforced, and local governments often still favor pollution-intensive projects that can generate economic growth.

Shijiazhuang, the capital of Hebei province, on Sunday ordered 20 percent of private vehicles off the roads in urban areas based license plate numbers, the official Xinhua News Agency reported.

On Friday, Beijing raised its pollution alert to the second-highest level for the first time, which meant some manufacturing plants had to suspend or reduce production, and that demolition work, barbecues and fireworks were banned. The alert was still in place Sunday. Trucks were spraying Beijing's roads, including in the financial district, as part of an increase in road cleaning, and more people than usual were wearing masks.

Xinhua said that almost all provinces in central and east China had had serious air pollution since Friday, and that Beijing and five provinces in northern and eastern China had reported "severe smog."

The National Meteorological Center said the pollution wasn't expected to clear until Thursday.