Two members of the LulzSec hacking group Monday pleaded guilty to attacking and disabling the Websites of several large organizations, including Central Intelligence Agency, Sony, Fox Entertainment Group, the Arizona State Police and Britain's Serious Organized Crime Agency (SOCA).
Ryan Cleary of Wickford, England, pleaded guilty to six of eight charges against him, while Davis, of Lerwick, England, admitted to two of the four charges against him.
The duo entered the guilty pleas in Britain's Southwark Crown Court today, according to Bloomberg Businessweek.
Both Cleary and Davis still face charges of posting unlawfully obtained data on sites such as PasteBin and Pirate Bay.
Two other alleged members of the group, Ryan Ackroyd and an unnamed 17-year-old individual, pleaded not guilty to all charges filed against them, Bloomberg and several British newspapers reported today.
All four are scheduled to be tried in April 2013.
Cleary was arrested in Britain last June in connection with a spate of high profile distributed denial of service attacks against numerous targets in the U.S and Britain.
He was initially charged with using a botnet to launch DDOS attacks against SOCA last year. He was also charged with attacking the International Federation of the Phonographic Industry (IFPI) site and the British Phonographic Industry (BPI) website in 2010.
Cleary also faces several charges in the United States. He was indicted by a federal grand jury earlier this month for DDoS attacks against Sony, Fox and other organizations.
U.S. authorities have said they will explore extradition options after the legal proceedings against Cleary in the United Kingdom are completed.
Cleary, who has Asperger's Syndrome, has been in jail since his arrest last June.
Davis, identified by police as alleged LulzSec spokesman "Topiary" was arrested in the Shetland Islands a few weeks after Cleary's arrest.
Police claimed that after Davis' arrest, they found incriminating evidence in a computer seized from his home.
The computer allegedly stored details of numerous pre-paid cards in false names, names and passwords of 750,000 random people, and drafts of a fake news story about media baron Rupert Murdoch's death which were used in attacks against Murdoch's News International publishing company.
LulzSec initially downplayed Cleary's arrest and maintained that police had got the wrong man.
A few weeks later, members of the splinter organization of the Anonymous hacking collective, issued a defiant statement vowing to carry on despite the arrests.
Several other members of LulzSec were arrested earlier this year based on information provided by Hector Monsegur, also known as 'Sabu,' a New York-based hacker who was identified by police as the leader of the group.
Monsegur, was quietly arrested by police last year, pleaded guility to multiple charges against him and agreed to work with the FBI in identifying other members of LulzSec and Anonymous.
Jaikumar Vijayan covers data security and privacy issues, financial services security and e-voting for Computerworld. Follow Jaikumar on Twitter at @jaivijayan, or subscribe to Jaikumar's RSS feed . His e-mail address is firstname.lastname@example.org.
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