A tour bus on a highway in Tibet fell off a 30ft cliff after crashing into two other vehicles, killing 44 people and injuring 11 others.
The bus was carrying 50 people at the time of the collision with an SUV and a truck in mountainous southern Tibet, China's official Xinhua News Agency said.
Most of the passengers were from four Chinese provinces. There were four people in the SUV and a truck driver, but their condition was unclear.
Police detained the managers of a travel agency and tour company connected with the bus trip, Xinhua said.
It said that the bodies and survivors were pulled out of the bus and the injured rushed to hospitals in the regional capital of Lhasa.
Tourism has been on the rise in the scenic Tibetan Plateau, where mountain roads are often treacherous and can be particularly dangerous in the summer rainy season.
The road where yesterday's crash occurred had a massive landslide earlier in the week, covering a 280-yard stretch in debris, according to China's weather services.