The passengers, residents of a village in Nanhua County of Chuxiong Yi Autonomous Prefecture, were on a tourist outing when the bus crashed in heavy rain, the Baosham publicity office said.
The injured were taken to local hospitals, two in critical condition, the official Xinhua news agency reported.
The Baoshan Public Security Bureau said initial indications showed the driver responsible for the accident, saying he operated the vehicle improperly in the rainstorm.
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