The Internet activist group Anonymous hacked two websites of the Federal Trade Commission (FTC) on Friday and posted a violent video satirizing the Anti-Counterfeiting Trade Agreement (ACTA).
The hackers attacked the FTC's Bureau of Consumer Protection’s Business Center and a site promoting the National Consumer Protection Week.
The main FTC webpage was unaffected.
Both sites were inaccessible by mid-morning.
The hackers replaced the government websites with a German-language video depicting a man in a ski mask gunning down people for downloading copyrighted music.
In a profanity-laced statement, Anonymous promised to "rain torrential hellfire down on all enemies of free speech, privacy and internet freedom" if ACTA is approved.
Anonymous has also crashed websites of the CIA and the Justice Department in recent weeks, but those attacks only overwhelmed the site's servers and did not actually replace the content of the sites.
ACTA is a multi-national trade agreement aimed at enforcing intellectual property rights.
The FTC, which focuses on consumer protection and competition issues, is uninvolved in ACTA. The Office of the U.S. Trade Representative is the agency responsible for negotiating the trade deal.