Hackers took down the sites by inflicting a denial of service, or DDoS, attack. The attacks were in retaliation for the shutdown of “The Pirate Bay,” a Sweden-based file-sharing website. Those charged ranged in age from 21 to 65 and lived in 13 different U.S. States. The group caused an estimated $5,000 in damages and affected at least 10 protected computers, court papers say. The suspects are charged with conspiracy to intentionally cause damage to protected computers.
Source: https://thehackernews.com/2013/10/13-anonymous-members-indicted-and.html