According to the indictment, Kernell used the alias "rubico" when he bragged about the hack online, then later tried to cover his tracks by deleting and changing files on his laptop computer.

Amateur Internet detectives linked Kernell to the rubico username shortly after the attack was made public. Several days later, Gabriel Ramuglia, the webmaster of a proxy service used by rubico to an Illinois company that provides Internet service to the Knoxville apartment complex where Kernell lives. The FBI searched Kernell's apartment on Sept. 21.

In a statement issued Wednesday by the U.S. Attorney's office in Knoxville, FBI Special Agent in Charge Richard Lambert applauded the help that sources provided authorities. "We would like to thank all of the internet service providers and others who partnered with us to bring this matter to a quick and successful resolution," he said.

If convicted, Kernell faces up to five years in prison and a fine of US$250,000.