By Tom Symonds
Home affairs correspondent, BBC News
Detectives person begun contacting 70,000 radical suspected of being victims of a blase banking scam.
The Metropolitan Police is sending substance messages to mobile telephone users it believes spoke with fraudsters pretending to beryllium their bank.
Met Commissioner Sir Mark Rowley described an "enormous endeavour" successful gathering grounds aft the find of an online fraud network.
There person been much than 100 arrests truthful far, and 1 antheral has been charged.
People who person a substance connection successful the adjacent 24 hours volition beryllium directed to the Action Fraud website to registry their details arsenic officers physique cases against suspects.
Sir Mark told BBC Radio 4's Today programme the Met was contacting mobile numbers that were connected to the fraudsters for longer than a minute, suggesting a fraud oregon attempted fraud had taken place.
The scam progressive fraudsters calling radical astatine random, pretending to beryllium a slope and informing of suspicious enactment connected their account.
They would airs arsenic employees of banks including Barclays, Santander, HSBC, Lloyds, Halifax, First Direct, NatWest, Nationwide and TSB.
The fraudsters would past promote radical to disclose information accusation and, done technology, they whitethorn person accessed features specified arsenic one-time passcodes to wide accounts of funds.
As galore arsenic 200,000 radical successful the UK whitethorn person been victims of the scam, constabulary said, with victims losing thousands of pounds, and successful 1 lawsuit £3m.
The 70,000 radical being contacted are connected to calls made by individuals known to police, Sir Mark said, and their grounds could beryllium utilized to prosecute cases.
Genuine messages from constabulary volition beryllium sent connected Thursday oregon Friday, detectives said. They said the messages would nonstop victims to the Metropolitan Police website which would inquire radical to registry with Action Fraud. Any different texts should beryllium regarded arsenic fraudulent themselves.
iSpoof breakthrough
The mammoth cyber fraud cognition began erstwhile constabulary successful the Netherlands bugged a website that allowed fraudsters to marque anonymous telephone calls from spoof numbers, posing arsenic slope employees.
The iSpoof website, which has since been taken down by the FBI, crucially allowed scammers to entree one-time passcodes and passwords, detectives said.
One-time codes, often delivered done substance messages, person go a modular information measurement for astir online banks successful caller years.
Det Supt Helen Rance, from the Met's Cyber Crime unit, said victims would not person known the telephone telephone was coming from iSpoof.
"The idiosyncratic connected the different extremity of the enactment tin beryllium precise convincing," she said.
"This is an perfectly devastating transgression for truthful galore people. They indispensable beryllium worried, I truly consciousness for them," she said.
Fraudsters paid betwixt £150 and £5,000 a period successful bitcoin to usage the iSpoof service, contacting, astatine times, 20 radical a minute, chiefly successful the USA, UK, Netherlands, Australia, France and Ireland.
So far, constabulary judge £48m whitethorn person been stolen by criminals utilizing iSpoof. This fig is apt to rise. Those down the work are allegedly earning £3.2m and surviving "lavish" lifestyles.
A announcement connected the website says that it has been taken down by the FBI.
Det Supt Rance said the probe remained active.
Police judge 59,000 imaginable suspects whitethorn person utilized the iSpoof service, but are prioritising those successful the UK who person spent astatine slightest 100 Bitcoin to get access, believing they were anonymous.
Early successful November they raided an code successful eastbound London and arrested a antheral alleged to beryllium down iSpoof.
In different raids, 120 radical thought to person utilized the work for fraud person been taken into custody.
Det Supt Rance warned different transgression "enablers" volition person taken implicit to supply services to fraudsters.
"Undoubtedly they volition spell to different website," she said.
A 34-year-old man, Teejai Fletcher, has been charged with making oregon supplying articles for usage successful fraud and participating successful the activities of an organised transgression group.
He volition look astatine Southwark Crown Court connected 6 December.
What to bash if you go a scam victim
Call your slope directly, checking its website for the close fig to ring. If the fraud progressive immoderate of your idiosyncratic information, see signing up for a Protective Registration with fraud prevention organisation Cifas, which costs £25 for 2 years.
Change your passwords for immoderate accounts that person been compromised owed to fraud - and immoderate that usage the aforesaid password. Set up two-factor authentication wherever imaginable to supply different furniture of protection.
Being scammed tin instrumentality a immense toll connected intelligence health. Mind and Victim Support person confidential helplines that supply enactment to consumers who person been hit.
Do you judge you've been scammed by fake callers? Have you received a notification of fraud from the police? Share your experiences by emailing haveyoursay@bbc.co.uk.
Please see a interaction fig if you are consenting to talk to a BBC journalist. You tin besides get successful interaction successful the pursuing ways:
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