New South Wales Police have charged seven people with 127 offences over the alleged sexual and physical abuse of three boys between 2014 and 2016 which included "blood rituals".

The charges have been laid against people linked to a performing arts school in regional NSW, the ABC has confirmed.

It is a community-based organisation whose participants include children with and without disabilities. It was established in 2009.

Detectives from the Child Abuse and Sex Crimes Squad set up Strike Force Baillieu in July last year to investigate reports of abuse on three boys under the age of eight, police said.

The ABC has been told police will allege the abuse allegedly involved sadistic sex acts and what police have termed "blood rituals" where blood was taken from the boys and they were forced to drink it.

A building where the performing arts school was based. ( ABC News: Kathleen Calderwood )

Police will allege the accused filmed the abuse and took photographs of the boys during the degrading acts.

The boys were known to the group and were not students of the performing arts school.

Police said there was no information to suggest there were any further victims, but detectives are appealing for anyone with concerns about suspected child abuse or exploitation to come forward.

Seven arrested for alleged abuse

Four women, two men and a 17-year-old girl have been arrested.

"Police will allege in court the group participated in ongoing sexual and physical abuse of three boys, who were known to them, between 2014 and 2016," a police statement said.

Lawyer Bryan Wrench, who is acting for all seven co-accused, told Penrith Local Court they denied all charges against them.

Mr Wrench said his clients were pleading not guilty at an early stage because they wanted it known there was more to the story than what NSW Police were alleging.

"I'd like it specifically noted that we're entering pleas of not guilty to all matters," he said.

"Simply to say 'we didn't do this'.

"This will be resolved in court."

Mr Wrench indicated all seven clients would apply for bail at a later date, saying they had known about the allegations since September and had been at liberty until Monday.

"They have always been ready to meet the police and we hope to get them bail."

A bail hearing has been set down for February 16 at Penrith Local Court.

More than 100 charges laid

A 58-year-old woman was charged with 43 offences, including aggravated sexual assault of a child under 10, have sexual intercourse with a child under 10, and aggravated kidnapping.

A 26-year-old woman was charged with 13 offences, including aggravated sex assault in company.

A 29-year-old woman was charged with offences including five counts of aggravated sexual assault.

A 52-year-old man was charged offences including three counts of aggravated sexual assault in company.

They were expected to face Penrith Local Court today.

A 17-year-old girl was charged with eight counts of aggravated sexual assault in company, aggravated kidnapping, and producing child abuse material.

An 18-year-old man was charged with 42 offences, including kidnapping, and sexual intercourse with a child under 10.

A 20-year-old woman was charged with offences including aggravated sexual assault and aggravated kidnapping.

They faced Parramatta Children's Court today.

The younger two did not apply for bail and it was formally refused.

The 20-year-old accused is still before the Children's court.