Ten passengers were killed and 24 injured -- seven critically -- after a bus plunged 30 meters down a ravine in south China's Yunnan Province Saturday, local police said Sunday.

The accident at about 12:40 p.m. occurred 10 meters from a sharp turn on a mountain road in rainy and foggy weather in Daqiao Township of Shiping County.

The bus, en route to Pu'er City from Kaiyuan City, veered off the 5-meter-wide road and overturned into the ravine when the driver was trying to avoid an oncoming truck, said passenger Bai Jijiang.

Five passengers died at the scene and five died of injuries later at hospital, said a police spokesman.

Twenty-three of the injured were being treated at two hospitals in Shiping and one had been transferred to a better hospital in Kaiyuan.

Of the 35 people aboard the 36-seat bus, only one was unharmed.

The bus belonged to the Honghe Transport Group, of Honghe Hani and Yi Autonomous Prefecture, which administers Shiping County and Kaiyuan City.

Police in Shiping are investigating the cause of the accident.