Warnings over door-to-door picture sellers
Households in Plymouth and Cornwall have been warned to beware of people asking them to buy paintings "to pay for an operation".
There have been a number of complaints throughout the areas about such door-to-door calls, police and Cornwall Trading Standards officers said.
In incidents, visitors have had a sign saying: "Deaf and dumb, need money for an operation, please buy my pictures".
Householders have been advised not to part with any money.
Martin Fisher, from Trading Standards, said: "We would urge the public to be particularly careful when dealing with any doorstep caller.
"Invariably, they charge way over the odds and don't give you the chance to shop around to find exactly what you want".
Devon and Cornwall Police added: "Anyone collecting door to door for charity needs to be registered with Cornwall Council.
"Before parting with any cash you should ask to see the paperwork granting them permission to raise money in this manner."