Read the first statement from the Church of Scientology here.

Read the second statement from the Church of Scientology here.

ALI MOORE, PRESENTER: An Australian resident has told Lateline the Church of Scientology imprisoned her on its cruise ship, The Freewinds.

Valeska Paris says the Church of Scientology's leader, David Miscavige, sent her to the ship when she was 18* to prevent her mother taking her away from Scientology.

Ms Paris says she ended up being on the ship for 12 years and was unable to leave The Freewinds for the first six years without an escort.

She's described the Church's leader as a psychopath and says he should be put on trial.

Steve Cannane has this exclusive report.

STEVE CANNANE, REPORTER: Valeska Paris was born into a Scientology family in Switzerland. At the age of six she moved to Scientology's headquarters in the UK and was placed in its then youth wing, the Cadet Org.

At 14 she joined the Church's elite Sea Organization, signing a contract binding her for a billion years.

It was a commitment that would override her bond with her own family. Valeska Paris says at seventeen the Church told her she could no longer see her mother.

VALESKA PARIS, FORMER SCIENTOLOGIST: I was basically pulled in and told that my mum had attacked the Church and that I needed to disconnect from her because she was suppressive. And ...

STEVE CANNANE: And what does that mean, to disconnect?

VALESKA PARIS: It means no connections at all with her or with anyone that she's connected to.

STEVE CANNANE: Her mother had denounced Scientology on French TV after her ex-husband, Albert Jaquier, had committed suicide. A self-made millionaire, his last days were spent in poverty. In a diary he kept, he blamed the Church of Scientology for fleecing him of his fortune.

Valeska Paris says the Church was so worried her mother would take her away that Scientology's leader David Miscavige intervened, ordering she be taken to the Church's cruise ship, The Freewinds.

VALESKA PARIS: He decided the ship. And I found out two hours before my plane left - I was woken up in the morning and I was sent to the ship for "two weeks".

STEVE CANNANE: And how long did that end up lasting?

VALESKA PARIS: 12 years.

STEVE CANNANE: Valeska Paris says she was held on The Freewinds against her will.

VALESKA PARIS: I did not want to be there. I made it clear that I didn't want to be there. And that was considered bad ethics, meaning it was considered not right.

STEVE CANNANE: Did you try to escape?

VALESKA PARIS: No, no.

STEVE CANNANE: Could you escape?

VALESKA PARIS: No. They take your passport when you go on the ship, so - and you're in the middle of an island, so it's a bit hard. And I was like - by that time I was 18. So, I didn't really - I'd been in Scientology my whole life. It's not like I knew how to escape and ... .

STEVE CANNANE: The Freewinds is used as a base to deliver Scientology's highest level counselling course, known as Operating Thetan Level Eight.

It cruises around the Caribbean, docking at small islands. The Church says ships have religious significance to Scientologists because its founder L. Ron Hubbard had researched and ministered the first Operating Thetan levels aboard a ship.

But for Valeska Paris, there was no freedom on The Freewinds. She says she was not allowed off the ship for the first six years without an escort and was forced to do hard labour in the engine room.

VALESKA PARIS: It's hot, it's extremely loud, it's smelly, it's not nice. But I was sent down there at first for 48 hours straight on almost no sleep and I had to work by myself. I wasn't allowed to work with anyone else. And I don't know if I went unconscious or if I fell asleep, but I was cleaning some part of an engine and it's extremely loud and I was just out for like four hours, and then this guy came and shook me four hours later and he said that I was unconscious.

STEVE CANNANE: The Church of Scientology in the US refused to be interviewed for this story. Their lawyers sent Lateline a letter threatening legal action over a breach of a confidentiality agreement between the Church and Valeska Paris. Valeska Paris says she signed this agreement under duress.

In a statement, the Church of Scientology said, "She certainly wasn't 'forced' to be there. She was also never forced to perform labour in the engine room. The Freewinds is a wonderful place, as even Valeska said on numerous occasions. Her allegation that she could only leave the ship with an escort is totally false."

RAMANA DIENES-BROWNING, FORMER SCIENTOLOGIST: Their response is a lie. Their response is a cover-up.

STEVE CANNANE: Ramana Dienes-Browning is a former a senior executive on The Freewinds. She was responsible for monitoring staff behaviour and performance on the ship.

RAMANA DIENES-BROWNING: She made it very clear she did not want to be there. You know, she had been sent to the ship so as not to be in contact with one of her parents and that's not what she wanted. She was very, very distressed.

STEVE CANNANE: Ramana Dienes-Browning is now working on a photographic exhibition re-enacting her time in Scientology. She says she too was held against her will on The Freewinds and suffered abuse.

RAMANA DIENES-BROWNING: I have been dealing with that trauma, and as a result I've experienced depression and post-traumatic stress and had to go through a process of dealing with that and healing.

STEVE CANNANE: In a statement, the Church of Scientology said, "We have no facts that would support Ms Dienes-Browning's opposite opinion."

Ramana Dienes-Browning says after five years of trying, she was finally able to leave the Sea Org and The Freewinds.

Valeska Paris left The Freewinds when she was sent to the Rehabilitation Project Force in Sydney. Scientologists describe the RPF as a voluntary religious retreat. Defectors describe it as a punitive re-education camp.

It was here she met former St George rugby league captain Chris Guider. Soon after, they got married and left the Church.

Valeska Paris says she'd like to see the head of the Church of Scientology, the man who she says sent her to The Freewinds, put on trial.

VALESKA PARIS: It's not right for someone to be running the Church and basically take advantage of, you know, a church and hiding behind religion to live like a king and to abuse people around him. That man doesn't like anyone. He's a psychopath.

STEVE CANNANE: The Church of Scientology denies their leader David Miscavige sent Valeska Paris to The Freewinds. When asked if this allegation was put to Mr Miscavige, the Church of Scientology failed to respond.

Steve Cannane, Lateline.

ALI MOORE: And the full statement from the Church of Scientology will be posted on our website shortly.

* Clarification: Valeska was 18 when she was sent to the ship, not 17 as originally stated. She was 17 when she was disconnected from her mother by the church.