Anonymous: 10 Facts About The Hacktivist Group

The FBI and U.S. Attorney's Office Tuesday announced that five principal members of the hacktivist groups Anonymous and its offshoot, LulzSec, have been arrested and charged. The men were located both in the United States and abroad.

According to the indictment, unsealed Tuesday in federal court in Manhattan, the charged men include Ryan Ackroyd (aka kayla, lol, lolspoon), Jake Davis (aka topiary, atopiary), Darren Martyn (aka pwnsauce, raepsauce, networkkitten), and Donncha O'Cearrbhail (aka Palladium). The men have been charged with hacking Fox Broadcasting Company, Sony Pictures Entertainment, and the Public Broadcasting Service (aka PBS).

According to the indictment, O'Cearrbhail was responsible for surreptitiously recording a conference call between the FBI and Scotland Yard in January. Parts of the call, released in early February, suggested that further arrests or charges were set to be made or announced within weeks, although some related details--such as suspects' names--were bleeped out of the recording.

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According to the indictment, O'Cearrbhail was able to join the conference call after hacking into the personal email account for an officer in Ireland's national police service, known as the An Garda Siochana (or Garda), who had made a security mistake. "Because the Garda officer had forwarded work emails to a personal account, O'Cearrbhail learned information about how to access a conference call that the Garda, the FBI, and other law enforcement agencies were planning to hold on January 17, 2012, regarding international investigations of Anonymous and other hacking groups," according to the indictment.

Meanwhile, authorities disclosed that Hector Xavier Monsegur, (aka Sabu, Xavier DeLeon, Leon) had been arrested last year, after which he agreed to work with the bureau as an informant. Furthermore, on August 15, 2011, according to the indictment, Monsegur pled guilty to a 12-count information charging him with computer hacking conspiracies, among other crimes. The charges related to hacks of HBGary and HBGary Federal, as well as Sony Pictures Entertainment and Fox Broadcasting. Authorities also charged him with hacking the Atlanta chapter of InfraGard, a private, non-profit group that exists to serve as a public/private partnership with the FBI.

A sixth man, Jeremy Hammond (aka Anarchaos, sup_g, burn, yohoho, POW, tylerknowsthis, crediblethreat), was arrested late Monday in Chicago and charged with hacking into the website global intelligence firm Strategic Forecasting, better known as Stratfor, in December 2011. Authorities said that Hammond had identified himself as a member of the LulzSec and Anonymous spin-off group AntiSec.

In the indictment, authorities sought to make clear connections between AntiSec and the other hacktivist groups. "In publicizing the Stratfor hack, members of AntiSec reaffirmed their connection to Anonymous and other related groups, including LulzSec. For example, AntiSec members published a document with links to the stolen Stratfor data entitled: 'Anonymous Lulzxmas rooting you proud' on a file sharing website," it read.

Law enforcement agencies had been steadily announcing the arrests of various LulzSec and Anonymous members. Notably, British police busted Jake Davis, an 18-year old living in the north of Scotland, and who authorities accused of being LulzSec's PR-savvy spokesman "Topiary," in July 2011. Meanwhile, at the beginning of September 2011, Scotland Yard arrested a man who they said was core LulzSec member Kayla, who was named in the indictment unsealed Tuesday as Ryan Ackroyd.

Sabu, however, appeared to remain at large, though he apparently granted an interview in October 2011, during which he disclosed that LulzSec and Anonymous still had a cache of hacked data from HSBC and Koch Brothers stored on a secret server in China.

But in fact, Sabu had been arrested before--and perhaps even helped authorities to positively identify--Ackroyd and Davis. According to Fox News, Monsegur (aka Sabu) was arrested by FBI agents in June 2011, after his identity was "doxed"--meaning he was named in an online post--earlier that month. The bureau accelerated its arrest plans, in case the identity disclosure spooked Monsegur into attempting to cover his tracks.

Authorities had put Monsegur under surveillance after he accidentally logged into a chat board without disguising his IP address. "He's extremely intelligent," a law enforcement official told Fox News. "Brilliant, but lazy."

The arrest revelation makes it clear why LulzSec called it quits in late June 2011, after a 50-day hacking spree: its anti-authority leader had been busted and turned informant.

Lazy or not, when it came to tripping up, the odds were apparently against the LulzSec crew. "When you're running this kind of operation for a long time, especially with not very concrete plans, you're bound to make mistakes," Tal Be'ery, lead Web researcher at Imperva, told USA Today last year.

"The mistakes LulzSec and Anonymous made during their hacking spree left an electronic trail with enough footprints to produce today's arrests," said Rob Rachwald, director of security strategy at Imperva, in a blog post.

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