Thick fog would shroud China's eastern and southern regions Sunday morning, the National Meteorological Center said, warning of increasing safety risks on roads and docks, as well as at airports.

The country's top meteorological authority issued a blue alert at 6 a.m, urging people in fog-affected areas to be aware of the air quality worsened by the fog and to reduce driving speeds to ensure safety.

Fog and haze would decrease visibility to within 1,000 meters in some parts of Jiangsu, Hunan, Jiangxi, Zhejiang, Fujian, Guangdong, Guangxi, Guizhou and Yunnan, and as low as 200 meters in worst-affected areas, the center said.