Heavy smog and haze is forecast to continue until Dec 8 in Nanjing, the capital of Jiangsu province, chinanews.com reported on Wednesday.

The report said Nanjing's air quality index on the morning of Wednesday stood at 338 - indicating severe pollution - and the Nanjing meteorological bureau has raised its alert from yellow to orange, the second most severe.

The report also said Nanjing's environmental protection authorities suggested residents avoid outdoor activities.