An overnight snowstorm has paralysed transportation systems in Chifeng city, Inner Mongolia, forcing highways and an airport to close, local authorities said Tuesday.

The snowstorm started at 6:00 PM Monday, with snow piling as high as 15 cm in some areas, the municipal weather department said.

Over 400 long-distance bus trips were canceled.

The city's Ningcheng county was among the worst hit areas.

Kang Ling, deputy director of the Inner Mongolia Meteorological Bureau, said the snowstorm was the second snowfall in the region this autumn.

The season's first snowfall came on Oct 11, 10 days earlier than average.

"The snow may harm the autumn harvests of corn and potatoes," she said.

Because of the snow, temperatures in the region plunged by about 10 degrees.

Chifeng is 485 km north of Beijing, the Chinese capital.

(Xinhua News Agency October 18, 2010)