Beijing has issued its second red alert for air pollution in December as a new bout of smog is forecast to hit the capital from Saturday to Tuesday.

The red alert, the most serious level, will last from 7.00 a.m. (local time) Saturday to 12.00 p.m. Tuesday, limiting vehicles on roads according to odd-even license plate numbers, Xinhua reported.

Fireworks and outdoor barbecue would be banned, the Beijing heavy pollution emergency response headquarters said on Friday.

Parts of north China will see the worst smog so far this year from Saturday, the National Meteorological Centre said on Thursday.

The air pollution will be > worse than the spell between December 6 and 9 it forecast.

Visibility in Beijing and some neighbouring regions will be reduced to less than one kilometre.

The density of PM2.5, particulate matter smaller than 2.5 mm used to measure air quality, in some of the regions will exceed 500 mg per cubic metre. The World Health Organisation’s recommended maximum is 25 mg per cubic metre.

Citizens were advised to reduce outdoor activities and kindergartens, primary and middle schools were expected to suspend classes during the alert.

>Beijing issued its first ever red alert for air pollution on December 7, when PM 2.5 reached the top of the scale at 500.