The public have been warned to be vigilant after a “vishing” scam cost victims more than £1 million in the past three weeks.
Police said a “small number” of people had been scammed out of £1.2 million in the north-east area.
Detective Inspector Iain McPhail, of the Economic Crime and Financial Investigation Unit, said: “Scams like these are completely sickening, with the criminal at the other end of the phone having no regard for their victim and the devastation their actions will cause.
“Pension pots and retirement funds can be stolen within a matter of minutes, with hard-earned savings wiped out without warning.
“Let me be clear that banks will never make phone calls like this asking you to move money, in particular into a foreign account.
“If you do receive such a call, hang up and call police immediately. You wouldn’t hand over your life savings to a stranger on the street, so you should never consider transferring money to a stranger on the other end of a phone.
“Banks will also never ask you to personally attend your local branch and make a transaction to a safe account.”
Anyone with concerns about scam calls should call police on 101.