Two British computer hackers have confessed to launching attacks on the NHS in the UK, and the CIA in America, with help from internet hacking group LulzSec.
Ryan Cleary, 20, from Essex and Jake Davis, 19, from the Shetland Islands, pleaded guilty at Southwark Crown Court to charges of conspiring to do an unauthorised act to impair the operation of computers.
They admitted using Distributed Denial of Service (DDoS) attacks to flood various websites with traffic to attempt to make them crash.
Targets for the DDoS attacks included the CIA, the Serious Organised Crime Agency (SOCA), News International and electronics giant, Sony.
The pair also admitted to hacking into the systems of the NHS, Nintendo, Sony and film studio 20th Century Fox among others, where they made changes to the websites, adjusting security settings and redirecting visitors to other sites.
They appeared in court alongside two co-conspirators, Ryan Ackroyd, 25, from Doncaster and a 17-year-old whose anonymity is protected for legal reasons, both of whom pleaded not guilty to the charges.
The four were caught after a joint operation between Scotland Yard and the FBI. Last year the front-man for LulzSec, Hector Xavier Monsegur or Sabu, was revealed to be an FBI informant.
Last year, LulzSec were responsible for hacking a website of Rupert Murdoch's News International and posting a spoof article stating that the media mogul was dead.
Cleary also admitted four further charges for acts which he carried out alone. In one of these attacks he hacked into computers at the US defence hub the Pentagon, where he altered files controlled by the US Air Force.
Cleary is under indictment in the US but his solicitor confirmed that he was not expected to be deported. He was remanded in custody, but the other three co-defendants were released on bail. The trial for the remaining charges will take place in April next year.
The NHS were informed of the hack last year on Twitter, but were quick to play down any risk to patient information.
"This is a local issue affecting a very small number of website administrators. No patient information has been compromised," a Department of Health spokesperson told the BBC at the time.