At least 38 people were injured, three severely, after a tourist bus flipped over and plunged into a ravine in central China's Henan Province Tuesday, local authorities said.

The accident took place at about 2 p.m. Tuesday on a mountain road in Xiuwu County, Jiaozuo City, when the bus was returning from a local scenic spot, said Qin Jie, a local publicity official.

Altogether 42 people were aboard the bus, including tourists, a bus driver and a tourist guide, when the accident happened, Qin said.

All the injured are being treated at three hospitals in Jiaozuo, he said.

"No deaths have been reported," he said.

The tourists were employees of a company in the eastern city of Qingdao, Shandong Province, and the bus was rented by a travel agency, he said.

An initial investigation shows that the bus was going too fast in a curve when it rolled down the ravine, he added.