The Church of Scientology has launched an online campaign against the BBC, ahead of the broadcast of a Panorama documentary investigating the organisation as a "cult".
Journalist John Sweeney has been targeted with a DVD made by the Church, which has distributed copies to MPs.
Sweeney got a little over-excited, during one encounter with the Church's followers, which was filmed, and posted on YouTube by a Scientologist. You might want to turn your speakers down a touch.
Sweeney has already apologised for the outburst. He told the Observer: "The moment it happened I said sorry. I let the side down and the BBC down and I am ashamed. But I felt I was being brainwashed and if people see the full clip I think they will have more sympathy with me."
The documentary's editor Sandy Smith fired back at Scientology's claims: "Their DVD contains two grossly defamatory claims about us - one, that we staged a demonstration against Scientology and two, that a terrorist death threat was made."
Scientology has a history of using the internet to further its agenda against psychiatry and in favour of believing in aliens. It has waged a long-running battle against anti-scientology site Operation Clambake, and other sites that reveal its top secret Xenu story. There's a history of Scientology's online battles at Wikipedia, or check out our related stories below.
Panorama is on BBC One tonight at 8.30pm. ®