Five hackers associated with cybercrimes were charged Tuesday after a key member of their loose-knit network was turned by the FBI and became a confidential informer, according to federal officials.
Federal prosecutors in New York unveiled the charges against five men — two from Britain, two from Ireland and one from Chicago — in connection with a string of cybercrimes in which hackers stole confidential information from U.S. companies and temporarily shut down government websites.
In a recent case, the hackers are alleged to have provided emails from Stratfor, a private intelligence company with close links to the U.S. government, to the antisecrecy group WikLeaks, which in February began publishing the emails online.
Officials said Tuesday that investigators were led to the five men, affiliated with the hacking group Anonymous, by Hector Xavier Monsegur, 28, a New York-based hacker who was arrested last June and began secretly working with the FBI to identify some of his cohorts.
"This is the most important roll-up of hackers ever," said Richard Stiennon, a cybersecurity analyst who has closely followed Anonymous. He said the investigation has injected "distrust into Anonymous" and, as a consequence, the FBI may have "broken the back of the collective."
The men were indicted on computer-hacking charges and other crimes by the U.S. Attorney's Office for the Southern District of New York. It was unclear how many of the European suspects had been arrested.
Still, senior law enforcement officials said that the case will take core members of the group offline and that more charges could follow.
A federal law enforcement official, who spoke to the Washington Post on the condition of anonymity because the investigation is ongoing, said Monsegur was identified after an apparent slipup in which he did not mask his Internet protocol address while he was online. Officials said the prospect of a long prison sentence later persuaded him to cooperate with the FBI.
Arrested Tuesday was Jeremy Hammond, 27, of Chicago, who is accused of breaking into the computer systems of Stratfor.
The others charged were identified as Donncha O'Cearrbhail, 19, of Birr, Ireland; Ryan Ackroyd, 23, of Doncaster, England; Jake Davis, 29, of the Shetland Islands, Scotland; and Darren Martyn, 25, of Galway, Ireland.
The four are accused of hacking into the computer systems of, among others, Fox Broadcasting, Sony Pictures Entertainment and PBS over the past year.