A British man has been extradited from Germany to face claims that he launched cyberattacks against Lloyds Banking Group and Barclays.
Daniel Kaye, 29, of Egham, Surrey, is accused of using an infected network to attack and blackmail the lenders, the National Crime Agency (NCA) said.
The NCA said Lloyds Banking Group – which includes Halifax Bank of Scotland as well as Lloyds Bank – saw services disrupted by an apparent cyberattack in January this year.
Barclays fended off an apparent cyberattack in the same month, it added.
Kaye also faces a claim that he “endangered human welfare” with an alleged cyberattack against Lonestar MTN, Liberia’s biggest internet provider.
It follows an investigation by the NCA and German authorities.
The agency said Kaye was returned to the UK on Wednesday by NCA officers under a European Arrest Warrant and remains in custody.
He is due to appear at Westminster Magistrates’ Court on Thursday.
Kaye faces nine charges under the Computer Misuse Act, two of blackmail and one of possession of criminal property.
Authorities allege he used a botnet called Mirai#14 against the banks.