Monsegur pleaded guilty in August to charges that included conspiracy to commit hacking, admitting he obtained dozens of credit card numbers online and gave them to others or used them to pay his bills.
His deal with prosecutors requires his full cooperation and testimony at any trial. In return, he gets leniency from a potential prison sentence of more than 120 years. He is free on $50,000 bail.
Also charged with conspiracy to commit computer hacking were Ryan Ackroyd, 23, of Doncaster, England; Jake Davis, 29, of Lerwick, Scotland; Darren Martyn, 25, of Galway, Ireland; Donncha O’Cearrbhail, 19, of Birr, Ireland; and Jeremy Hammond, 27, of Chicago. The Europeans were previously arrested in separate hacking cases, though two of them were re-arrested on Tuesday.
Hammond, who was arrested Monday, appeared before a federal judge in Chicago and was ordered transferred to New York. Hammond was charged with crimes related to the hacking in December of Strategic Forecasting Inc., a global intelligence firm in Austin, Texas, that affected up to 860,000 victims.
In July, when LulzSec’s attacks were grabbing world headlines, someone alleged that Sabu was Monsegur and posted personal details about him on the Internet. Sabu took to Twitter to deny it.
Barrett Brown, a former journalist who became closely associated with Anonymous, said Sabu’s cooperation with the FBI could do serious damage to Anonymous.
“He was an admired Anon,” he said. “He’s been a leader. People came to him with information. God knows what else he told them.”
Associated Press writer Satter reported from London. Also contributing were Associated Press writers Colleen Long and David B. Caruso in New York and Michael Tarm in Chicago.
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