BEIJING, Dec. 13 (Xinhua) -- Cities in China's north experienced serious air pollution in November as heating service began for the winter, according to the Ministry of Environmental Protection.

Six cities in Beijing's neighboring Hebei Province, including Xingtai, Baoding, Shijiazhuang, Langfang, Tangshan and Hengshui, were among the 10 cities with the most polluted air, together with Jinan in Shandong Province and the northeastern cities of Shenyang, Harbin and Changchun, according to the monthly report issued by the ministry on Sunday.

Shenyang had the most polluted air in November, according to the report that reviews air quality in 74 Chinese cities.

The ministry said 34 of the 36 cities in the northeastern provinces of Liaoning, Jilin and Heilongjiang were severely polluted starting from Nov. 1 to Nov. 14, while 10 of the 13 cities in the Beijing-Tianjin-Hebei region saw heavy pollution in late November.

Luo Yi, director of the ministry's Department of Environmental Monitoring, said air quality in the regions of Pearl River Delta and the Yangtze River Delta had improved in November compared with the same period last year.

The ministry also named 10 cities with the best air quality in November. All in southern China, they included Haikou, Xiamen, Zhoushan, Fuzhou, Guiyang, Huizhou, Lishui, Nanchang, Kunming and Shenzhen.