How scammers defrauded 750 victims - mainly solicitors and accountants - in one of UK's biggest cyber fraud scams
The fraudsters behind a £113 million (€131.68m) international money laundering ring used their ill-gotten gains to fund a lavish lifestyle of fast cars and five-star hotels.
Described by police as one of the biggest cyber fraud scams ever investigated in the UK, the gang made between £1 million and £2 million a week at its peak and operated like a nine-to-five business.
They targeted Lloyds and RBS business banking customers in a cold-calling scam and police believe they were using information from corrupt insiders.
Police said no insiders from within the RBS banking group were discovered, but three Lloyds insiders have been convicted.
The scam was derailed following a investigation involving Scotland Yard's Fraud and Linked Crime Online Taskforce (Falcon) and 16 police forces across the country between April and October last year.
Some 750 victims - mainly solicitors and accountants - were defrauded by the gang, which was headed by Feezan Hameed, a British-Pakistani based in Glasgow.
The 23-year-old ringleader would claim to be a member of the bank fraud department when he called customers, before persuading them to reveal their internet banking details in a "very persuasive, very articulate" manner, Scotland Yard said.
While Hameed kept victims talking, his associates would gain access to their bank accounts and empty them.
The fraudsters used a "network of money mules" to disperse the cash before it was laundered to Dubai and Pakistan.
Between January 2013 and October 2015 the gang took £113 million from victims, of which £47 million has been recovered. The outstanding £66 million is believed to have been laundered from the UK.
A solicitors' firm lost more than £2.1 million in a hit, several companies nearly went bankrupt and one victim who handed over details to the scammers during a call later committed suicide.
Detective Chief Inspector Andrew Gould said: "When they were at their height - when they'd really got the hang of this - they were probably making one to two million quid a week.
"It was a Monday to Friday, nine-to-five operation, and when they were busy and active they were just smashing victims all day, every day, running their criminal business like a proper business."
The gang were extremely sophisticated in their techniques, displaying false telephone numbers on the phones of victims and disposing of pre-paid phones and dongles once they had completed a hit.
Ringleader Hameed kept clear of the cash and was treated with "respect and deference" by the rest of the group, despite only being in his twenties.
"He is very much the controlling guy, totally in charge," DCI Gould said.
"The kind of guy that when he flies to Dubai for a weekend shopping with his chums - they all fly economy, he flies first-class."
The money funded a lifestyle of luxury and fancy cars, with the group spotted in Bentleys, Range Rovers, a Rolls-Royce and a lime green Lamborghini.
After months of surveillance, scores of arrests were made on October 21 but Hameed evaded authorities and travelled to France.
He was arrested as he attempted to board a flight to Pakistan with a fake passport at Charles de Gaulle airport in Paris on November 13 - the night of the Paris attacks.
After the gang were charged, police recruited the help of one of the offenders who provided crucial evidence to bring the group and its ringleader to justice.
"I think it was the assisted offender who persuaded pretty much most of the top guys to plead guilty," DCI Gould said.
He added: "This was the largest covert proactive operation the Met has ever undertaken against cyber-enabled crime.
"It demonstrates our commitment and ability to dismantle organised criminal networks in order to keep businesses safe from this type of crime."
An RBS spokesman said: "This vishing scam is an example of how sophisticated fraudsters' tactics can be.
"With any suspicious or unexpected call, always verify the caller using an independently-checked telephone number and use a different phone line where possible.
"Where a second phone line is not available, try calling a friend on the line first. The fraudster will find it difficult to impersonate a voice that is known to you.
"We take our customers' security very seriously and each reported fraud case is looked at on an individual basis and investigated thoroughly.
"We'd advise all of our customers to familiarise themselves with guidance on keeping safe from scams that we have available online at www.rbs.co.uk/security."
A spokesman from Lloyds said: "We take the issue of fraud very seriously and safeguarding our customers' money is of paramount importance.
"As soon as we became aware that the three colleagues were involved in fraudulent activity, they were suspended and subsequently dismissed."