The fraud involved a man pretending to be a police sergeant who phoned a woman and told her about two men being arrested.
Ultimately, the woman was conned out of almost Â£10,000.
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How the scam was carried out
A man claiming to be a Police Seargeant for Humberside Police phoned a woman. He told her that he was part of an undercover operation and that they have arrested two men who they believed had withdrawn Â£16,000 in cash from her bank account, before replacing it with fake money.
They then told her someone in the bank may be involved and they required the victim's help to rectify the situation.
The caller - the fake policeman - then told the victim she would need to go to the bank and withdraw Â£9,200 in cash to check if some of the counterfeit money was in the account.
What happened next
The 'officer' then persuaded the woman, aged in her 70s, to withdraw the money from her account, asking her to tell the bank that she was buying a car.
The 'officer' told her he would come by to take the money using the password 'MOORE'.
A man attended, provided the password and the victim handed over the money.
The incident happened in Harrogate and began at 2pm on April 10 and is being investigated by North Yorkshire Police.
What police are saying as advice
âš ï¸ These heartless fraudsters typically prey on the elderly and pretend to be police officers to gain their victims’ trust.
âš ï¸ The police or your bank will never ask you to withdraw or transfer money from your bank account to aid an investigation.
âš ï¸ Please be extra cautious if you receive a call of this nature and never give out or confirm personal or financial information to anyone over the phone.
âš ï¸ If you have any suspicions at all do not engage in conversation and please hang up the phone. They will try to cause panic and fear to get you to collect money for them.
"Investigations are ongoing and the victim is being supported by officers.
"If you believe you have been a victim of this type of crime, call us on 101 or report it to Action Fraud by visiting actionfraud.police.uk or by calling 0300 123 2040. In an emergency dial 999. If you have any information regarding those responsible for such crimes, contact Crimestoppers on 0800 555 111.
"More advice on how to protect yourself and your family from fraudsters can be found by visiting northyorkshire.police.uk/fraud"