Ryan Cleary, the Briton arrested on suspicion of being part of the LulzSec hacking group, has been indicted by a federal grand jury in Los Angeles.
The 20-year-old is currently in custody in the UK and has now been accused by US prosecutors of hacking into a number of websites, including Sony, Fox and the PBS television network. He is already facing similar charges in the UK.
He stands accused of using a network of compromised computers, known as a botnet, to launch attacks on websites. It is alleged he used his hacking skills to access websites to deface them or steal valuable user data.
Laura Eimiller, an FBI spokeswoman, said: "Cleary is a skilled hacker. He controlled his own botnet, employed sophisticated methods and his broad geographic scope affected a large number of businesses and individuals."
Cleary is charged with one count of conspiracy and two counts of unauthorised impairment of a protected computer. He faces a maximum sentence of 25 years in prison if convicted.
LulzSec was an offshoot of hacker collective Anonymous, which hit the headlines during 2009 and 2010 for a string of attacks on organisations it claimed were restricting freedom of expression on the internet.
Its victims included MasterCard and Visa, whose sites were knocked offline by a distributed denial of service (DDoS) attack after they refused to accept donations for WikiLeaks following the publication of thousands of highly secret US diplomatic cables.
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Other victims include the UK serious organised crime agency (SOCA), the FBI and the CIA. In a highly embarrassing move, Anonymous managed to record and publish a conference call between British and US police, which discussed legal actions planned against hackers. The group obtained an email sent on 13 January to various law enforcement agents that contained the date, time, phone number and the access code needed for the conference call.
Earlier this year it was revealed that Sabu, the alleged leader of LulzSec, was in fact an FBI informant. According to Fox News, he was turned after being arrested in June 2011 and provided details of Anonymous and LulzSec members in return for avoiding jail.
The FBI has even suggested that Sabu was helped by the FBI to facilitate the release of millions of emails hacked from intelligence company Stratfor. You can read more about that case here.
