Authorities in China's Tibet Autonomous Region say the death toll from a powerful earthquake has risen to 126.

Officials also say the magnitude-6.8 tremor that hit Tingri County on Tuesday morning left 188 people injured.

State-run China Central Television reported that the quake damaged more than 3,600 houses and displaced around 30,000 people.

The affected areas are more than 4,000 meters above sea level. Communities near the epicenter have traditional houses made of mud bricks.

Firefighters and military personnel are searching people trapped under collapsed buildings.

But search operations and evacuations of residents are facing challenges.

Aftershocks with magnitude of 3 or higher are continuing, and overnight temperatures fall to minus 18 degrees Celsius.