The organised criminal network, led by Glasgow resident Feezan Hameed and his brother Nouman Chaudhary, targeted thousands of Lloyds and RBS business banking customers using sophisticated ‘social engineering’ techniques to persuade the businesses to reveal their internet banking details.

Ten other individuals connected with the case were sentenced earlier in the year, receiving sentences totalling over 12 years.

Hameed was responsible for cold calling the victims; purporting to be from their bank’s fraud department and using various aliases, he was able to dupe customers into revealing online account information which enabled him and his associates - based around the country - to access hundreds of online business accounts and steal vast sums of money.

Three corrupt bank employees were also recruited to the gang, who supplied customers’ account details and helped launder the money.

On receipt of the mark’s internet banking details, the gang would log into the account, transferring large amounts of cash into ‘mule accounts’ under the gang’s control. These sums would be quickly siphoned through the banking system into further mule accounts before being withdrawn in cash from ATMs and bank branches around the UK, often within hours of the original fraud.

Between January 2013 and October 2015 the crooks looted £113 million from over 750 victims, of which £47 million has been recovered. Detectives believe most of the outstanding £66 million has been laundered from the UK to Dubai and Pakistan.

In many cases victims were defrauded of hundreds of thousands of pounds, with several businesses nearly going bankrupt as a result. One victim alone lost over £2 million.

At raids on premises across the UK, police recovered over £120,000 cash, gold bars, over 100 bank cards with PINs in other people’s names, card readers, dongles, SIM cards, mobile phones and laptops.

Detective chief inspector Andrew Gould, head of the Met's Falcon cybercrime taskforce says: "This was the largest covert proactive operation the Met has ever undertaken against cyber-enabled crime. Customers can protect themselves by always exercising caution when called by someone claiming to be from their bank, even if the number they are ringing from appears to be genuine. Telephone numbers are easily faked. If a bank believes your account is being compromised they will act to prevent this without asking for your assistance."