Mario Anzuoni / REUTERS file Gene Simmons was among the targets of a hacking group outraged at the closure of a file-sharing site called "The Pirate Bay," according to a federal indictment. Simmons had spoken out against music piracy.

Thirteen alleged members of the computer hacking group Anonymous were indicted Thursday on conspiracy charges accusing them of coordinated cyberattacks on anti-piracy groups, government agencies, credit card companies and others, dubbed Operation Payback.

The federal grand jury indictment, filed in federal court in Alexandria, Va., alleges that the 13 used distributed denial of service, or DDoS, attacks against the websites of the Motion Picture Association of America, the Recording Industry Association of America, Kiss founding member and reality TV star Gene Simmons, and Hustler magazine, among others.

Read the federal indictment

The attacks, the indictment says, initially were in retaliation for the shutdown of “The Pirate Bay,” a Sweden-based file-sharing website used to illegally download copyrighted material.

The 13 defendants were identified as: Dennis Owen Collins, Jeremy Leroy Heller, Zhiwei Chen, Joshua S. Phy, Ryan Russell Gubele, Robert Audubon Whitfield, Anthony Tadros, Geoffrey Kenneth Commander, Phillip Garrett Simpson, Austen l. Stamm, Timothy Robert McClain, Wade Carl Williams, and Thomas J. Bell. They lived in a variety of states, and it wasn't clear if they were custody.

The defendants were involved in Operation Payback between September 2010 and January 2011, according to the indictment. On Sept. 16, 2010, a flier was posted on a Web bulletin board advertising an attack on the MPAA: "We target the bastard group that has thus far led this charge against our websites, like The Pirate Bay. We target MPAA.ORG!" The first attack was launched the next day, the indictment said.

Over the next several weeks, according to the indictment, DDoS attacks targeted websites of organizations that had spoken out against piracy of intellectual property. That included groups based in Britain, India, Italy, France and the Netherlands. Later attacks came against the U.S. Copyright Office, Warner Brothers, Bank of America and MasterCard and Visa.

Simmons' website was attacked because he had spoken out against music piracy, the indictment alleges. Internet fliers were distributed stating: "Mr.Simmons shares the same ideology as ACS:Law and many of our other targets. Thusly his website has been targeted." ACS:Law was a British legal firm that specialized in intellectual property law.

Simmons spoke out against piracy at a music industry conference in October 2010. "The music industry was asleep at the wheel and didn't have the balls to sue every fresh-faced, freckle-faced college kid who downloaded material," Simmons said at the MIPCOM conference in Cannes, France, according to ArsTechnica.

In December 2011, federal authorities in California charged another man with involvement in the attacks on Simmons. Kevin George Poe pleaded guilty this January and was sentenced to home detention and probation.

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