A 19-year-old New Jersey man has pleaded guilty to knocking the Church of Scientology's Web site offline in a series of January 2008 online attacks.

Dmitriy Guzner, of Verona, New Jersey, was part of an underground hacking group called Anonymous that has made the church a target of several attacks. He had been expected to enter a guilty plea when he was charged last October, but it was not formally entered until Monday, the U.S. Department of Justice said in a statement.

He faces 10 years in prison on computer hacking charges and is set to be sentenced on Aug. 24 in U.S. District Court for the District of New Jersey.

The attacks began Jan. 19 and managed to knock the Scientology.org Web site offline by hitting it with several bursts of unwanted Internet traffic. Called a distributed denial of service (DDOS) attack, it flooded the site with as much as 220Mb per second of traffic.

Anonymous promoted the incident with several YouTube videos. "For the good of your followers, for the good of mankind and for our own enjoyment, we shall proceed to expel you from the Internet and systematically dismantle the Church of Scientology in its present form," a creepy computerized voice says in one Anonymous video.