Lancaster Police have sent out a warning to all shopkeepers and staff after reports of fraudsters in the area.
People coming from outside the Lancaster, Morecambe and Carnforth areas are attempting to defraud shops out of money.
This is done by asking to change large quantities of notes into smaller denominations of notes.
If anybody is made aware of this or is asked to change large quantities of notes into smaller denominations then refuse point blank and inform the police on 101.
The police have said if they leave in a vehicle to please obtain the registration plate.