Police are warning people to be aware of bogus police officers after people were tricked into giving out their bank details.
A woman in her 80s gave out her details after receiving a phone call from a man claiming to be a detective chief inspector from the Metropolitan Police.
The caller, who claimed he was DCI Charlston, told her she had been the victim of a fraud and that he needed all her bank details, which she provided.
The woman, who is from Chigwell, was then told that the officer would need to see her bank cards and that a courier would be sent to collect them.
A man turned up 30 minutes later and took the cards.
It is not yet known how much has been taken from the woman’s savings.
Detectives are carrying out an investigation into the incident which was reported on Tuesday morning.
Inspector Paul Wells said: "It is absolutely vital that people are on their guard if they receive a call of this kind.
"Genuine police officers will never ask for bank details over the telephone.
"It is possible that one man or a group of criminals working together is using different names and different stories to trick the elderly or vulnerable.
"One simple rule will prevent you from falling for this kind of con and that is to never give bank details to anyone who has called you.
"The same is true of people who knock at your door. If an individual is legitimate, they should not mind your asking for them to prove who they are.”
Anyone who is contacted by a caller claiming to be police investigating a bank card fraud should contact police on 101.
Anyone with information about suspicious callers claiming to be police should call detectives at Loughton CID, also on 101