Criminals are using a new scam to make people believe they are speaking to someone from their bank by fooling their phone handset into displaying the bank’s correct contact number.

The scam, known as “number spoofing”, involves fraudsters cloning the telephone number of an organisation they want to impersonate and then making it appear on the victim’s caller ID display when they telephone them.

The Financial Fraud Bureau, which has issued a warning to consumers, said criminals are using number spoofing to gain victims’ trust, often by drawing their attention to the number, in a bid to make them believe they are talking to their bank.

In recent years a number of criminal gangs have taken to the phones in a bid to persuade the unwary into handing over their life savings. The fraudsters call people up out of the blue and pose as bank staff, police officers or other trusted organisations to persuade their victim to part with financial and personal details – often on the pretence that fraud has been detected on their account.

In many cases the criminal asks the customer to call the bank on the number on the back of the bank card – the same number displayed on their handset. In fact, the fraudsters simply keep the phone line open and play a fake dialling tone down the line.

The victims, who think they are talking to their bank, are then told to move their money to a secure account. In other cases, victims have been told to hand over their debit or credit cards to a courier. Victims have lost thousands of pounds, some in excess of £100,000.

While the technology needed to spoof someone’s number has existed for years, criminals have only recently begun using it to defraud people. Financial Fraud Action UK’s intelligence unit – the Financial Fraud Bureau - said it has become increasingly common in recent weeks.

The FFA said: “If a number appears on your phone’s caller ID display, you shouldn’t assume you know where the call is being made from. Remember that if a caller is trying to draw your attention to the number on your phone display, it’s very unlikely the call is genuine as there is no legitimate reason to point it out.”

He said the advice to beat the scam is simple – never assume that someone is who they say they are just because their number matches that of an organisation you know. You should be suspicious if you’re asked for your four digit Pin, your full online banking passwords, to transfer or withdraw money, or to give your card to a courier. Your bank or the police will never ask you to do any of these things.

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