BEIJING - Beijing and its adjacent area have issued an orange alert for heavy air pollution as smog looks set to linger for the next three days.

The orange alert, the second highest in the four-tier warning system, will be effective from midnight Wednesday in Beijing. The capital is forecast to see serious air pollution from Thursday to Saturday.

Beijing Vice Mayor Zhang Gong ordered implementation of full emergency measures, including restrictions on coal burning, production and heavy trucks.

Outdoor activities in schools should be canceled, and construction projects will be suspended.

Central and southern areas of neighboring Hebei upgraded its pollution alert from yellow to orange on Tuesday midnight. The provincial capital, Shijiazhuang, began to restrict cars on roads according to odd and even plate numbers on Wednesday.

Handan City in Hebei ordered industrial companies to cut emissions by at least 30 percent.

In Anyang City, Henan Province, car restrictions were adopted and free buses are offered through Sunday.

The smog is expected to disperse Sunday when a cold front is forecast to arrive in north China.