Smog alert issued as official urges action

Beijing's environmental authority has issued an orange alert for smog - its second-highest warning level - with heavy air pollution forecast to persist until Wednesday night.

The weather is due mostly to unfavorable conditions for the dispersal of pollutants, the Beijing Environmental Protection Bureau said.

Elementary and secondary schools have been advised to stop outdoor activities, while trucks transporting construction waste, muck, sand and gravel have been banned from the capital's roads while the alert is in place.