Fifteen minutes after the government made arrests and shut down the file-sharing website Megaupload yesterday, several government and entertainment industry websites began to fail, including the homepages for the FBI and the Department of Justice. The underground hacking collective Anonymous quickly took credit, tweeting that it was responsible for its “largest attack ever,” with 5,635 involved in bringing down the sites. “The FBI didn’t think they would get away with this did they?” said members of the group ina statement that was later tweeted. “They should have expected us.”

Other affected websites included the Recording Industry Association of America, the Motion Picture Association of America,, and Universal Music, though all the sites were back up and running by Thursday night. “The motion picture and television industry has always been a strong supporter of free speech,” an MPAA spokesman said, in a statement to the Associated Press. “We strongly condemn any attempts to silence any groups or individuals.”

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