A search for the bodies of stillborn babies is underway at the headquarters of secretive religious sect Twelve Tribes.

Two police raids at Peppercorn Creek Farm in Picton and at a 78.5-hectare property near Bigga, south-west of Sydney, began on Monday.

The operation is part of an ongoing investigation into the high number of stillbirths within the community which rejects modern medicine and technology.

Three graves have been uncovered at the Bigga site which has no running water or electricity and is only used when members are exiled for questioning their beliefs, A Current Affair reported.

Police raids began at Peppercorn Creek Farm in Picton and a 78.5-hectare property near Bigga (pictured), southwest of Sydney, on Monday

It is illegal to bury a body without registering the death with the Registry of Births, Deaths and Marriages.

Council permission is also required to bury a body on private property.

The operation is expected to continue over the coming days.

A police spokeswoman told Daily Mail Australia no on has been arrested.

The search follows a six-hour raid at the Picton property on February 19.

Daily Mail Australia has contacted Twelve Tribes for comment.

Three graves have been uncovered at the Bigga property. Pictured: What is believed to be the grave of a stillborn baby

Peppercorn Creek Farm, south-west of Sydney, is the headquarters of Twelve Tribes

The raid comes after former member Rosemary Cruzado told the publication her late-term stillborn baby was buried at the Bigga property.

She believes her baby's death could have been avoided if she had seen a modern doctor earlier in her pregnancy.

Twelve Tribes has been investigated by police since September 2019.

The sect is a registered religious charity and has been in Australia since the '90s.

It has about 90 members in its Picton, Katoomba and Coledale communes and runs cafes in Sydney and the Blue Mountains.

The cult does not align itself with any denomination.

Members believe the Messiah will return if the church is restored to its original form in the Book of Acts - the first book in the new testament of the Bible.

Twelve Tribes has been guarded about its privacy and members are expected to live by a set of rigid guidelines which govern almost every aspect of their lives.

Communication with the outside world is largely forbidden.

Or Mathias, 26, left the cult more than eight years ago

Women are expected to be subservient to men and everyone must marry within the group.

Children are home-schooled and raised on the back of a 300-page manual which insists they are obedient, do not question their superiors, are forbidden from playing with toys or the make-believe and are to be spanked with a 50cm rod for any indiscretions.

Or Mathias, 26, left the cult more than eight years ago and previously told The Sunday Telegraph he spent the first six years of his life living in a Brazilian commune with 'strange men' before finally moving to the Picton branch in south-west Sydney.

Mr Mathias said while he keeps in contact with plenty of ex-members, most are too afraid to speak out.

He claims he was beaten with a thin rod and forced to work from a young age. He was also given limited opportunities for an education.

Mr Mathias claims he watched an eight month old baby be disciplined during his time with the Picton sect because she cried at the dinner table.

Andrew McLeod, who manages one of the sect's many cafes in the Blue Mountains and is an original member of the Australian branch of the group, previously said allegations of child abuse and child labour were untrue.

'We want our children to have a well-balanced life and what we do and our beliefs have somehow been taken out of context to portray us as a fundamentalist cult that bashes our children, which is just not true,' he said.

'It's sad that so many people are gullible enough to believe what they believe without looking into it themselves.'