Seven elderly people have been targeted in a month by fraudsters who asked for their PIN numbers.

Three victims lost money after being taken in by the scammers, who sent couriers or taxi drivers to their houses to collect their bank cards.

The incidents all took place between February 24 and March 23.

Courier fraud scammers telephone victims claiming to be from an authority such as the police, a bank or the Serious Fraud Office and tell them their bank account has been compromised and their card must be collected.

They then ask the victims to hang up and call the authority on a genuine number, but they do not disconnect and remain on the line.

The suspects ask them to reveal their PIN, usually by typing, and collect their bank cards.

Det Supt Ellie O’Connor, from Redbridge police, said: “These unscrupulous people target the most vulnerable members of our communities and prey on their trusting nature. Please know that my officers will never ask anyone for their bank card or their PIN number.

“The effects of becoming a victim of this despicable crime run far deeper than a loss of cash. Please work with us to ensure those you care for have the confidence to hang up on anyone mentioning their PIN and save them the anguish of falling victim to thieves.“

If you are contacted by someone asking for your PIN or bank card, hang up and use a different line to report the crime to police on 101.

Alternatively, wait at least five minutes for the line to automatically clear.

If a crime is still taking place, call 999.