The UK citizen allegedly responsible for launching the Mirai botnet against banks has been extradited from Germany to the United Kingdom.
Daniel Kaye, of Egham, Surrey, has been accused of launching a series of cyberattacks against the Lloyds and Barclays banking groups over the course of two days in January this year, disrupting online banking systems used by Lloyds, Halifax, and Bank of Scotland customers.
Barclays faced a similar attack in the same month but was able to push it back.
The 29-year-old is accused of launching the Distributed Denial-of-Service (DDoS) attacks against the financial institutes, which smashed the banks' systems with fake requests to the point that legitimate traffic could not get through.
It is believed that Lloyds received a ransom demand of £75,000 in Bitcoin to halt the disruption, but the company did not comply.
The cyberattackers were allegedly made possible through the Mirai#14 botnet, which harnesses and enslaves vulnerable computers and Internet of Things (IoT) devices which are then forced to send the fake traffic requests.
Following an investigation by the National Crime Agency (NCA) and German BKA, Kaye is now being charged with being responsible for these attacks under the UK Computer Misuse Act. Kaye faces nine charges under the act, as well as two counts of blackmail and one of possession of criminal property.
A Lloyds Banking Group spokesperson said the attack was "successfully defended" and no customer details were compromised.
The NCA says that the suspect is also facing a charge of "endangering human welfare" through conducting a cyberattack against Liberian Internet provider Lonestar MTN.
As reported by the BBC, the court heard that in an email to one potential client, Kaye boasted that there were between 555,000 and 1.5 million computers enslaved to his network.
Kaye, a dual British and Israeli citizen, was extradited under a European Arrest Warrant and is in custody until a plea and case management hearing on 28 September.
"The investigation leading to these charges was complex and crossed borders. Our cyber crime officers have analyzed reams of data on the way," said Luke Wyllie, senior operations manager at the NCA. "Cyber crime is not victimless and we are determined to bring suspects before the courts."