At least eight people have been killed in an avalanche that struck a tunnel exit near the south-eastern Tibetan city of Nyingchi on Tuesday night.
Many cars were overturned by the avalanche, which left the road covered in snow, a local resident who joined the rescue effort told local media.
It is unclear how many people are missing. Hundreds of rescuers and 30 large machines are searching the scene.
Avalanches happen frequently in the mountainous region.
The avalanche happened on a highway connecting the town of Pai in Mainling county and Medog county in Tibet, a remote and mainly Buddhist region in western China.
One woman told local media outlet Hongxin News that her husband was missing after the accident. He had been on his way to the airport to fly home to celebrate Lunar New Year together.
With an average elevation of about 3,100m above sea level, Nyingchi is a popular travel destination.
In October, at least 26 people were killed in an avalanche on Mount Draupadi ka Danda in northern India during a mountaineering expedition.