Three ex-Lloyds TSB employees made a series of bank transfers using stolen log-in details while working for the bank.
The scam involved the use of a ‘high-tech' device which was installed on a colleague's computer and used to steal private details to make fraudulent transfers, the Old Bailey has heard.
The three men who are on trial and deny the charges are: Tai Hulbert-Thomas, 27, from Oxford, Neil Bautista, 22, of Maidenhead and Mawli Thurairajah, 30, of Harrow.
"[The case] involves three fraudulent actions on Lloyds banking group through a technological device that was placed on to the internal account work station in three Halifax branches - Slough, Newbury and Camden," prosecutor James Thacker said.
"The device allowed remote access into the secure banking systems that led to fraudulent transfers being made by the criminal group, causing significant loss to the bank," he added.
Thacker explained that although the gang attempted to steal £2m, the actual loss to the bank was just over £440,000.
He said that the technological device "left footprints which we can look at".
An internal investigation was called after a Halifax branch manager in Slough was made aware of a suspicious transaction of £50,000 into a customer's account. A further 12 accounts had also received fraudulent credits.
The investigation found that a rouge USB mouse, keyboard and mass storage device had been planted on one of the desktops at the branch. The device enabled remote access to the computer through the internet.
The trial continues.
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