A member of a loosely organized group of hackers accused of breaching computer networks of the FBI and a global intelligence firm pleaded guilty Tuesday to conspiracy charges, officials said.
The US Justice Department said Jeremy Hammond, known by his handle "Anarchaos," pleaded guilty in Manhattan federal court for his role in the December 2011 hack of the intelligence firm Stratfor.
Officials said Hammond pleaded guilty to one count of conspiracy and also admitted his involvement in computer intrusions into the FBI Virtual Academy, the Arizona Department of Public Safety and other government networks.
Hammond was among five people indicted in 2012 alleged to be members of Anonymous, Lulz Security and other international hacking groups.
The indictments cover some of the most notorious hacking incidents of the past several years including those against Sony Pictures Entertainment, Stratfor and computer security firm HBGary.
"While he billed himself as fighting for an anarchist cause, in reality, Jeremy Hammond caused personal and financial chaos for individuals whose identities and money he took and for companies whose businesses he decided he didn't like," US Attorney Preet Bharara said in a statement after the plea.
"He was nothing more than a repeat offender cybercriminal who thought that because of his computer savvy he was above the law that binds and protects all of us."
Hammond, in a statement posted on the freejeremy.net website, said he made a "difficult decision" to accept a "non-cooperating plea agreement" that allows him to discuss the case.
He said that "there were numerous problems with the government's case, including the credibility of FBI informant Hector Monsegur."
But he maintained that "because prosecutors stacked the charges with inflated damages figures, I was looking at a sentencing guideline range of over 30 years if I lost at trial."
Hammond added that, even if he were acquitted, "the government claimed that there were eight other outstanding indictments against me from jurisdictions scattered throughout the country... I would likely have been shipped across the country to face new but similar charges in a different district. The process might have repeated indefinitely."
Hammond faces up to 10 years in prison on the charge in sentencing set for September 6. Officials said he also agreed to pay up to $2.5 million in restitution.
Authorities said Hammond and the other defendants "stole confidential information from those computer systems, including Stratfor employees' emails as well as account information for approximately 860,000 Stratfor subscribers or clients."
The hackers stole data from some 60,000 credit card users and used some of the stolen data to make more than $700,000 in unauthorized charges, officials said.
Charges are still pending against Britons Ryan Ackroyd and Jake Davis; Darren Martyn, of Galway, Ireland; and Donncha O'Cearrbhail, of Birr, Ireland.
At the time of the indictment, officials said the hackers were involved in attacks on videogame maker Bethesda Softworks, the Irish political party Fine Gael, the Fox Broadcasting Company and the Public Broadcasting Service.
Explore further: Pinterest buys startup with image organizing skills