Drivers in Bath claim they are being forced to pay ‘protection’ to stop their cars being vandalised.
It is understood that if motorists do not hand over cash to strangers hundreds of pounds worth of damage is being done to their cars.
One man told the BBC that he refused to pay money to someone who approached him as he paid for a ticket at a car park.
When he returned to his car it had been badly damaged and police are now calling for more victims to come forward.
The incident is said to have happened in a council-owned car park and now Bath and North East Somerset Council is investigating the matter.
Motorist Stewart Barratt told the BBC: ‘I've only refused [to pay] once and I came back to my car and it was damaged, £385 it cost me to put it right.
‘My car had been urinated over, wing mirrors were broken and the wiper blades back and front were ripped off.’
Another victim, Tommy Ferris, said: ‘You feel very intimidated and it's frightening when there are a group of people shouting abuse at you.
‘If you park your car somewhere, you expect it to be safe, especially somewhere like this. Not only is it a commercial car park, it's within yards of a police station.’
A statement from Avon and Somerset Police said: ‘We are aware of one incident where a motorist was asked for money before somebody urinated on his car.
‘No other incidents have been reported recently.
‘Officers regularly patrol the car park, making several visits everyday and often ask individuals to move on.
‘Anyone who has been threatened or had their car vandalised should report the matter to police immediately.’