A group of internet users calling themselves "Anonymous" are gearing up to destroy the Church of Scientology.

Anonymous has posted a message on YouTube declaring open war on Scientology and has named February 10 as a worldwide day of protest. The group is accusing the controversial church of trying to censor the internet and conducting "campaigns of misinformation".

According to online reports, the apparent catalyst for the attack was YouTube's decision to remove a video of a seemingly crazed Tom Cruise espousing the religion's virtues. The video was pulled on the advice of the Church of Scientology.

"Anonymous has therefore decided that your organisation should be destroyed, for the good of your followers, for the good of mankind, and for our own enjoyment", says the group's statement. 

"We shall proceed to expel you from the internet and systematically dismantle the Church of Scientology in its present form," it continues.

The message, read by a computerised voice and set against a grey cityscape, finishes with the ominous statement: "We are Anonymous. We are legion. We do not forgive. We do not forget. Expect us."

According to a report in The Age, last week several major Scientology websites crashed in the United States and Britain. The FBI was asked to investigate after envelopes of white powder were sent to 19 Scientology churches in the Los Angeles area.

While Scientology websites now appear to be functioning normally, Anonymous, which has warned "that it does not expect its campaign to be completed in a short time frame", may yet be saving its largest attack for February 10.

Scientologists be warned.