Overnight in Kangding, a mountainous region in Sichuan's western highlands, mudslides took down some homes in a village, killing two, while 12 were missing, national broadcaster CCTV reported.

A bridge connecting two tunnels on an expressway linking Kangding and Ya'an collapsed on Saturday morning, causing three vehicles to fall off the highway. One of the six passengers has been rescued, CCTV said. It did not specify whether they had fallen off the bridge.

China has been roiled by record rain and heatwaves this summer as scientists warn of more extreme weather fuelled by climate change. In the past decade, Sichuan and Hunan in the south have suffered the most damage from storms and floods, reporting cumulative economic losses of more than 100 billion yuan ($14 billion) each, according to some estimates.

In Zixing, a city in Hunan province, 30 residents died after Typhoon Gaemi lashed the region with record rains in late July. Local officials said on Friday that 35 people were still missing.

Across Hunan, the rains induced by China's most powerful typhoon so far this year have affected 1.15 million people and caused direct economic losses of about 6 billion yuan.

A highway bridge collapse triggered by flash floods in the northwestern province of Shaanxi killed 38 people, local authorities said on Friday in their latest tally of fatalities.

Despite search and rescue work in the past two weeks, 24 people remained missing after the Shaanxi bridge collapse, which plunged 25 vehicles into a river.