Victims were asked to send more money to release their winnings from being held at UK airports and were persuaded to send personal cheques to UK 'agents', which turned out to be other victims who unknowingly laundered the money to overseas scammers.
The OFT says that a genuine prize draw, sweepstake or lottery would never ask people for any kind of tax or fee to release winnings.
Meanwhile, people have been warned to watch out for emails from a company called Parcel Delivery Service telling them they have missed a parcel delivery.
People are asked to call an 0906 number to arrange delivery but are connected to a premium rate line charging at least £15.
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