Police in the city of Yichang received a report last night from a bus driver who said that his passengers - a group of 23 independent travellers - had not returned from the Huangniuyan Scenic Spot near the Three Gorges Dam.
The travellers entered the tourist site last morning, the driver said, adding that contact with the group was lost in the evening, state-run Xinhua news agency reported.
Authorities have launched search operations to locate the tourists.
Municipal firefighters are working with local residents to search for the missing tourists.