Three officers from the force were attending a webinar held on Wednesday, October 14 to offer crime prevention advice.
In the last three months, Cambridgeshire police have been working on a new development around a fraud that’s picking up momentum across the Eastern regions of the country.
They said there has been an increase in scams of buying and selling of vehicles and issued words of caution to prospective buyers and sellers, warning that "there are many fraudsters out there".
One of the officers recalled an incident recently where the victim lost nearly £11,000.
PC Trevor Craig, the lead investigator of vehicle fraud for the force said: "If you are selling your car privately, do not give them the keys if they want to take it alone for test drive.
"We have been hearing reports of suspects asking for keys when coming to buy the car. Then taking it for a test drive, closing the keys and returning the cloned key back. And later in the night they are returning to steal the car. It's all over the eastern regions."
The officers advised the public to follow the guidance issued on the Action Fraud website, which can be found here.