People who fell victim to a scam offering devices that were claimed to help them get cheap electricity have been warned they may be targeted again.
Trading Standards reported several consumers have received phone calls from the criminals, purporting to be working for the authorities and warning them their device is unsafe.
They are then asked to pay around £300 to cover administration costs in order to receive compensation, which never arrives.
Sue Jones of Westminster Council's Trading Standards said: "Just like with the first scam where consumers are cold called to buy the energy savings device, the caller appears very credible and has a lot of information about the person they are calling."
Last December, the body warned many people had been offered plug-in devices that were incorrectly said to be able to cut energy usage by up to 40 per cent.
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