Scammers have been posing as police officers to trick people into handing over money.
Hertfordshire Constabulary says it has received further reports of scam calls this week and is urging people to be vigilant of them.
The force said that in some cases, elderly residents have sadly been tricked into handing over money to fraudsters.
Typically, victims are contacted by callers posing as police officers, from either a landline or a mobile number, informing them that there has been fraudulent activity on their bank account.
The bogus police officer then asks victims to withdraw cash, or in some cases to buy expensive items, to hand over to a courier that is despatched to their address.
The scammers may also ask people to assist the investigation by handing over bank cards and disclosing their bank details, including their account and PIN numbers.
Usually, the intended victim realises the call is not genuine and refuses to part with their details or cash.
However, police have warned these fraudsters can be very persuasive and insistent, which has resulted in some people falling victim to this scam and subsequently losing thousands of pounds.
Police say the vital things to remember are that your bank and the police would:
Never ask for your bank account details or PIN over the phone, so do not disclose these to anyone, no matter who they claim to be.
Never ask you to withdraw money and send it to them via a courier, taxi or by any other means.
Never ask you to send your bank cards, or any other personal property, to them via courier, taxi or by any other means.
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