China says 8 northern cities failed air quality targets in Oct., Nov.

FILE PHOTO: People are seen amid heavy fog on the outskirts of Changzhi, Shanxi province March 19, 2010. REUTERS/Stringer/File Photo

BEIJING (Reuters) - Eight northern Chinese cities failed to meet air quality targets in October and November, even as local authorities launched rigorous steps to cut emissions during the winter, the government said on Monday.

The failures highlight the challenge Beijing faces in cleaning the nation's notoriously toxic air during the winter when smog blankets colder regions as people crank up their heating.