The FBI says it is investigating why the websites for the FBI, the Department of Justice, and several entertainment industry sites all went down Thursday after the government shut down one of the world's largest file-sharing sites.
The hackers' group calling itself "Anonymous" claimed credit for the attacks, which kept the sites offline for several hours late Thursday. By Friday, most had been restored to service, including the federal agencies.
Earlier Thursday, U.S. federal authorities shut down the file-sharing site known as Megaupload and charged its founder and six others with violating piracy laws.
Megaupload founder Kim Dotcom ((aka Kim Schmitz)) was arrested in New Zealand Thursday along with three other top executives at the request of U.S. authorities. Three others facing charges remain at large.
A statement by the U.S. Justice Department and FBI said the action is "among the largest criminal copyright cases" ever brought by the United States. If found guilty, the suspects face up to 20 years in prison. Authorities say Megaupload cost copyright holders more than $500 million.
Megaupload allowed users to upload and transfer very large files. Federal officials say the website used this ability to make copyrighted material, like Hollywood movies, available for free, often before the film was even released in theaters.
But the company, and many celebrity supporters, say the site was mainly used for legitimate file transfers.