The multinational group supports file sharing and is known for denial-of-service attacks that crash or overwhelm sites, and the grand jury indictment says its first target was the MPAA. Thirteen suspected U.S. members of Anonymous face conspiracy charges tied to the loose-knit group’s “Operation Payback,” an effort launched three years ago in response to the shutdown Swedish file-sharing site Pirate Bay, the indictment says. The filing quotes one set of Anonymous instructions as saying: “This will be a calm, coordinated display of blood. We will not be merciful.” The charges, filed Thursday in U.S. District Court in Alexandria, VA, cover attacks on government, credit card and lobbying sites. A half-dozen suspected leaders of the group were indicted in March 2012.

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