Twenty people were confirmed dead and 42 were missing Sunday after mudslides engulfed several villages in southwest China, state press reported.

The mud and rock flows occurred near Chuxiong city in Yunnan province with the exact number of people killed still being counted, Xinhua news agency said, citing local authorities.

According to the local government, up to 300 people live in the area where the slides occurred, the China News Service said.

Xinhua said the landslides began early Sunday morning and flattened or damaged more than 1,000 houses.

It was not immediately known what caused the slides, but torrential rain pummelled the region throughout Sunday and was expected to continue for the coming days, China Central Television reported.

According to Xinhua, most of the missing were from Xinhuadazhulin village, where three people were confirmed dead and 33 people were missing, an earlier report said.

Six people were confirmed dead in Baodian village, while another three were killed in Duoyi village, it added.

Rescue teams have been dispatched to the area and are frantically looking for the missing, it said.

Yunnan is a mountainous province that sits next to the Himalayan region of Tibet, where landslides frequently occur due to torrential rains or earthquakes.

The province also neighbours Sichuan, where an 8.0-magnitude earthquake centred in the Himalayan foothills left over 87,000 people dead or missing in May this year.

In September, 276 people were killed in northern China's Shanxi province when an industrial waste reservoir situated on a mountainside collapsed and engulfed a village in a sea of mud, rocks and mine tailings.