Isis could be behind your cold calls. Really.

British pensioners are being targeted in a new scam to raise funds for Isis, with extremists posing as police officers to trick elderly people into handing over their bank details.

One elderly man has already been conned out of £150,000 as a result.

A major investigation into fraud and money laundering by police resulted in three men being arrested yesterday over the alleged scam by extremists travelling to Syria.

The fraud targeted “unsuspecting vulnerable and elderly victims” who were called at home by someone claiming to be a police officer, according to Scotland Yard. Victims were told their bank account had been compromised and were encouraged to transfer money to an account under the control of the fraudsters.

In a statement, the Metropolitan Police said: “Officers are investigating a large-scale fraud linked to UK extremists travelling to Syria.” The three men – aged 23, 29 and 37 – were arrested on suspicion of money laundering during searches at addresses in London yesterday.

The arrests come just months after Detective Chief Superintendent Terri Nicholson, from the Met’s Counter Terrorism Command, warned: “We are seeing diverse fraud including substantial fraud online, abuse of the benefits system, abuse of student loans, in order to fund terrorism.”

The flow of money from Britain is part of a wider picture which has seen Isis become the world’s richest terrorist group – with more than £1bn to its name thanks to the oil fields it seized in Iraq, and millions made from kidnapping, looting and the smuggling of antiquities.

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