In an open letter to a senior Scientology official that has been posted on the Internet, Ms Jenna Miscavige Hill described how her family was broken apart by the policies of the movement.

Her father is Mr Ron Miscavige, the older brother of Mr David Miscavige.

'Hell, if Scientology can't keep his family together - then why on earth should anyone believe the church helps bring families together,' she wrote.

Ms Hill, 23, wrote the letter after Scientology attacked writer Andrew Morton's book Tom Cruise: An Unauthorised Biography.

The actor is a vocal advocate for the movement and the book gives it extensive coverage.

In a 15-page statement issued on Jan 14, Ms Karin Pouw, the movement's public affairs director, denounced the book as a 'bigoted defamatory assault replete with lies'.

But in her reply to that statement, Ms Hill retorted: 'I am absolutely shocked at how vehemently you insist upon not only denying the truths that have been stated about the church in that biography, but then take it a step further and tell outright lies.'

In particular, she challenges Scientology's denial that it puts pressure on members to break all contact with relatives who do not support the movement - a practice known as disconnection.

She said it was this policy that broke up her own family.

'As you well know, my parents officially left the church when I was 16 in 2000,' she wrote. Having been separated from them since the age of 12, she decided not to go with them.

But she added: 'Not only was I not allowed to speak to them, I was also not allowed to answer a phone for well over a year, in case it was them calling me.'

She was allowed to visit her parents only once a year for a maximum of four days, she wrote - and then only after her parents threatened legal action to get access.

Asked about Ms Hill's statement, Ms Pouw told AFP: 'The church stands by its statement of Jan 14. The church does not respond to newsgroup postings.'

When contacted by AFP, Ms Hill said she had circulated the letter to draw attention to the practice of disconnection.

'My intention is to put it on a public forum so they are pressured into changing their ways - even if it is just to cover for themselves.'

Morton's book is currently at the top of the New York Times bestseller list for hardback non-fiction after its first week on sale.

AFP