Guangxi's meteorological observatory raised the blue fog warning to yellow at 7:30 am on Dec 24.

Visibility is less than 500 meters in cities such as Hechi, Baise, Chongzuo, Nanning, Fangchenggang, Qinzhou, Beihai and Guigang. Parts of the areas have smoke fog with visibility less than 200 meters.

The fog is expected to last the whole day.

Nanning, capital of Guangxi Zhuang autonomous region, is meshed in the dense fog on Dec 24. [Photo by Zhou Hua / Xinhua]

Edited by Andrew Ancheta