Have you received one of these letters?
We're being warned of a scam circulating in Swansea.
Letters from a firm called Marston Holdings claim the householder owes money, sometimes running into thousands of pounds.
Police are urging people to report the letters to their action Fraud department.
We were forwarded the letter by a Sketty woman who wishes to remain anonymous.
She said: "We got this official looking letter this morning telling us if we didn't pay £1,121 they'd send the heavy mob around.
"We called the police and they rang us back to say they were logging it in as a fraud/scam incident. They said on no account let anybody into your home. They said to log in with their Action Fraud department.
"We owe nobody a thing. If we owed council tax we would have had a letter from CCS telling us to pay by instalments or something.
"If we hadn't been compus mentis, it would have frightened the life out of us and we would have written a cheque immediately.
"Some poor people out there are losing money."