A gang of thieves broke into the London offices of Sumitomo Mitsui Banking Corporation and installed keylogging software on computers in a daring plot to steal £229 million, a court has been told.
In 2004 a security supervisor helped two computer hackers enter the bank's offices and install the spyware to record employee usernames and passwords, the jury at Snaresbrook Crown Court heard.
The thieves allegedly returned days later to collect the passwords before attempting to make over 20 electronic transfers from the accounts of Sumitomo customers such as Nomura Asset Management and Toshiba.
The money was intended for accounts around the world, including Dubai, Hong Kong and Singapore, which were controlled by accomplices, jurors were told. But the transfers failed because of an error in the order forms.
The plot was uncovered after staff noticed that their computers had been tampered with.
The security guard, Kevin O'Donoghue, and hackers, Jan Van Osselaer and Gilles Poelvoorde, both from Belgium, have admitted their roles in the conspiracy.
However, three other men are on trial accused of acting as fronts, setting up companies and bank accounts designed to receive the stolen money.
Hugh Rodley, David Nash and Inger Malmros deny conspiracy to defraud and conspiracy to transfer criminal property. Another defendant died shortly before the trial.
The case continues.