The Huade County fire department in the Inner Mongolia Autonomous Region said both vehicles rolled upon impact, Xinhua News Agency reported.
The state-run news agency said the truck driver and two passengers on the bus died at the scene and a third bus passenger died later at a hospital. The 36 injured passengers were all taken to hospitals.
The bus was en route from Xilinhot City to the regional capital of Hohhot when the accident occurred about 1 a.m. at an intersection in Huade County.
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