Says he was 'purposefully blind' and only regret is waiting so long to leave

Haggis, 61, split from the church in 2009 after being a devotee for 35 years

Claims he was trolled by Scientologists so can't trust

Paul Haggis spoke about how he was trolled online by Scientologists after he very publicly renounced the organisation in 2009, describing it as a cult

Oscar-winning film director and former Scientologist Paul Haggis has described how followers of the controversial religion uses the internet to attack people and 'ruin their careers'.

In an interview with The Telegraph, 61-year-old Haggis spoke about how he was trolled online by Scientologists after he very publicly renounced the organisation in 2009.

'I know what they do online,' he said. 'I've seen them attack others under false names, try to discredit them, ruin their careers.

'And I've heard about these two people who work in the basement of Special Affairs there and they're just online all day at their computers, going on to various blogs, commenting on people's lives and things they do.'

The filmmaker, who is the only person ever to have won the Oscar for best picture two years in a row, said the trolling has forced him to ignore what is written online about his films.

Speaking to The Telegraph's Hermione Hoby, Haggis pointed out that Wikipedia had banned Scientologists from commenting.

'So when people comment on me or my films, yes there's a part of me that goes, 'Well that could be absolutely valid or that could be a Scientologist,' he said.

Haggis' filmography includes 2004's Million Dollar Baby, Casino Royale and crime drama Crash, as well as his upcoming romantic thriller Third Person.

But he has almost become more famous for his explosive parting with the Church of Scientology after 35 years - subsequently denouncing it as a 'cult', and openly discussing the organisation in a 2011 interview with The New Yorker.

His resignation letter, which was leaked to the press, denounced the church's support for Proposition 8, which banned same-sex marriage in California.

According to reports, he said that he could no longer remain part 'of an organisation where gay-bashing was tolerated'.

The Church of Scientology - which counts Hollywood actors Tom Cruise, John Travolta and Kirstie Alley among its members - was founded by the science fiction writer L Ron Hubbard in 1953.

The religion, which is based around the idea that humans are ‘immortal beings’ who have forgotten their true nature, has been at the centre of a number of controversies.

It has often been branded a cult although church leaders have repeatedly denied it brainwashes adherents.

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A Church of Scientology building in Florida. The religion - which counts Hollywood actors Tom Cruise, John Travolta and Kirstie Alley among its members - was founded by science fiction writer L Ron Hubbard in 1953

Haggis told The New Yorker that a few days after sending his resignation letter, he returned home from work to find nine or ten church members standing in his front garden.

In the days that followed, more members and various officials visited his office, distracting his colleagues and becoming 'more livid and irrational' as he refused to change his mind.

But Haggis told The Telegraph that he doesn't feel it took courage to leave the notoriously secretive organisation and he has no regrets about leaving Scientology when he did.

Haggis' filmography includes 2004's Clint Eastwood-directed Million Dollar Baby (pictured) starring Hilary Swank, Casino Royale and crime drama Crash, as well as his upcoming romantic thriller Third Person

He added: 'Except waiting so long. Being so stupid for so long. But it's really insidious.

‘I was always an outsider and if it can affect me that much – a cynic and a loner and an outsider – go figure! You have to be really purposefully blind, you have to choose to be blind, and that’s what I was doing and that’s what all my friends were doing.’