A narrowboat crashed into a Land Rover in the River Avon between Cleeve Prior and Harvington, Worcestershire, at around 11.50am on Thursday.
West Mercia Police were called after an unoccupied submerged red Landrover Freelander was hit.
The occupiers of the canal boat which crashed into the Land Rover called the police, worried that the vehicle may have had someone inside it.
The police service, along with the Hereford and Worcester Fire Service brought the occupiers of the boat to shore.
The Land Rover was also brought to shore and was thoroughly searched.
It is reported that the Land Rover may have been pushed into the water.
A spokesman for the West Mercia Police said: "Police officers would like to thank local landowners and businesses and other river users for their cooperation.
They also would like help finding the owner of the vehicle and how it came to be in the river."