After a noteworthy lack of action on during the SOPA blackouts on January 18th, it seems that Anonymous is springing back into action in response to the federal takedown of MegaUpload and the subsequent arrest and likely extradition of Kim Dotcom. Just hours after the news that the U.S. federal government took down MegaUpload alongside an indictment on piracy charges, Universal.com and Justice.gov have gone down, and a prominent Anonymous affiliated Twitter account is claiming responsibility.

ALERT: Recording Industry Association of America RIAA.ORG TANGO DOWN #Megaupload — AnonOps (@anonops) January 19, 2012

Get some popcorn… it’s going to be a long lulzy night. — Anonymous (@YourAnonNews) January 19, 2012

Knowing Anonymous, there is probably more to come both in the way of DDOS attacks and threats toward the federal government, SOPA supporters, and other organizations that have spearheaded copyright infringement lawsuits. More as the story develops.

5:17 P.M. Update: RIAA.org is now down.

5:28 Update 2: and MPAA.org.

5:55 Update 3: Tweets indicate there may be more attacks to come this evening.

7:47 Update 4: Anonymous is reporting FBI.gov as down. Some people report being able to get through, but the site is clearly under a lot of stress.

8:19 Update 5: Now it’s definitely down. FBI.gov, that is. MPAA and RIAA sites are back now though.

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