Cheap electricity customers are being targeted by fraudsters offering discount top-ups to people with pre-payment meters installed in their homes.
According to the Mirror, more than 165,000 households have been hit by con artists offering top-ups for less than they would pay through official outlets, typically handing over £25 for £50 credit.
Fraudsters use a cloned key to put the extra credits on the victim's meter, which show up immediately.
However, energy suppliers are spotting these illegal credits and will force customers to pay for the energy they have used at the full rate, the newspaper reports.
Energy UK director Christine McGourty told the paper that the cheap energy industry has launched a number of measures to crack down on 'meter cheaters'.
She mentioned that the Top-up Safe campaign, which provides information about protecting homes from scammers, has led to energy providers working together to prevent pre-payment fraud.
"But the number of incidents continues to rise as more people fall victim to this serious scam," she warned.
"The people selling these illegal top-ups are criminals and although it might seem like an easy way to save money, not only will you be letting a criminal into your home, but you will also end up having to pay twice."
Pre-payment meter credit should be purchased instead from the Post Office, official PayPoint and Payzone retailers.
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