Police said that the 55-seat bus had 61 people on board when the bus veered off road and overturned in Gannan Tibetan Autonomous Prefecture at around 1:20 a.m. Monday. Among them, 12 were minors, but none of them was among the dead.
The survivors have been taken to hospitals in Gannan. Four people are still in critical conditions and put under intensive care.
The coach left Wenshan, Southwest China's Yunnan, for Gansu's capital Lanzhou on Sunday. The passengers were all migrant workers with their kids, who were going to work in Lanzhou.