Beijing has issued this year’s first red alert for heavy air pollution. The pollution is expected to start from 8 p.m. tonight and may last until Wednesday.

The red alert is the highest level of China’s four-tier alert system for air pollution. It comes as heavy air pollution is forecast to sweep Beijing and its surrounding areas.

Local authorities say vehicles will be restricted based on an odd-or-even license plate rule and high polluting vehicles will be ordered off the roads.

Governments and state-owned enterprises are required to cut the number of vehicles on the road by 30 percent. The city will also shut down construction sites and certain factories, while schools are advised to suspend classes.