The death toll in southwest China's Tibet Autonomous Region from Saturday's earthquake in neighboring Nepal has risen to 25, according to the regional disaster relief headquarters.

A total of 117 there sustained injuries, it said.

A 8.1-magnitude quake shook Nepal at 2:11 pm (Beijing Time) on Saturday, which also affected the southwestern part of Tibet, especially Xigaze City.

The city has 18 counties and prefectures, and a population of more than 700,000. The counties of Gyirong, Nyalam and Tingri were most affected. Nearly 80 percent of the houses in these three counties collapsed.

The number of casualties is likely to increase as access and communication returns to normal, a spokesperson of the headquarters said.

"We worry most about Zham Town. Rescue work there is particularly difficult because the road to the town is blocked," said Mayor of Xigaze City Zhang Hongbo.

Zhang added that Zham Town has felt more than 20 aftershocks, which have caused landslides and avalanches.

The town is in short supply of food and bottled water. Food stocks will likely only last three days.

A 37-km highway linking Nyalam County with Zham has been blocked by multiple landslides.

Rescuers are still working to clear an important tunnel that winds through high mountains.

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