The fraud involves only electricity, not gas, pre-payment meters. It’s believed that the criminals have cloned the keys for these meters, allowing them to top them up illegally.
However, energy companies can identify homes using electricity but not paying for it, so make sure you only buy your electricity credit from official outlets such as the Post Office, PayPoint or Payzone.
The scam has now spread nationwide, with more than 114,000 customers so far affected.
The worst affected areas range from big cities like London, Birmingham and Manchester to areas such as Thurrock and Southend-on-Sea.
The electricity top-up scam is of particular concern as to get the fake top-ups people must let the criminals into their homes to access their electricity meters. There have also been reports of threatening behaviour.
Christine McGourty, Director of Energy UK, said: "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, you will end up having to pay twice. The only people benefitting from this scam are the fraudsters and the only way to get the energy you pay for is to buy top-ups from official PayPoint and Payzone retailers or the Post Office."
If you’re offered cut-price electricity top-ups, say no and report it to Action Fraud by following the link below or by calling 0300 123 2040.
You can also report a possible fraud to your energy company, Consumer Direct on 08454 04 05 06 or Crimestoppers anonymously on 0800 555 111
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