In a hastily assembled retaliation against the federal shutdown of MegaUpload.com, hacktivist group Anonymous has allegedly taken down a number of websites--including those of the U.S. Department of Justice, the Motion Picture Association of America (MPAA), and the Recording Industry Association of America (RIAA).

According to DownForEveryoneOrJustMe.com, several websites are out of commission as of this writing, likely thanks to DDoS attacks: the U.S. Department of Justice (doj.gov, justice.gov), the U.S. Copyright Office, Universal Music Group, the RIAA, and the MPAA.

At about 2 p.m. on Thursday, @AnonDaily, a Twitter account assumed to be associated with Anonymous, tweeted: "TANGO DOWN! JUSTICE.gov - U.S. Government Website DOWN!" The account has continued to post updates, noting that RIAA, MPAA, Universal Music Group, and U.S. Copyright Office websites were all down, and that Anonymous istrying to knock out several other websites, including the FBI and White House websites.

They are also working on taking down the website of MPAA chief, Chris Dodd, who is a strong supporter of the controversial Stop Online Piracy Act (SOPA) and Protect IP Act (PIPA) bills that are currently making their ways through the congressional circuit. Dodd said Tuesday that yesterday's Internet blackout protests performed by big Web players, including Google and Wikipedia, were an "abuse of power."

Here's what's offline right now, as of 4pm PST:

U.S. Department of Justice

U.S. Copyright Office

Recording Industry Association of America

Motion Picture Association of America

Universal Music Group

BMI Music

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