One by one, they were rounded up and taken into custody. Eight family members across three states, arrested by police following a six year investigation into suspected historic and ongoing child abuse in New South Wales.

The alleged offenders include a man and woman in the Griffith area who were taken to Griffith Police Station.

The 45-year-old man was charged with six counts of sexual intercourse with a child under 10, four counts of indecent assault, sexual intercourse with a child aged between 10-14, aggravated act of indecency, and common assault.

These images show the home of the "Colt" family in the Griffith area. (9news)

People were arrested in South Australia, Western Australia and New South Wales. (9news)

This image appears to show a sleeping area in the home. (9news)

The 38-year-old woman was charged with perjury. Both will appear in court later today.

The investigation involved police in three states.

In the Riverland region of South Australia, a man and two women were arrested and taken to Berri Police Station. A 29-year-old man was charged with a NSW arrest warrant for two counts of incest with a person under the age of 16 years.

The investigation into the case date back to 2012. (9news)

Eight family members were arrested across three states. (9news)

The Griffith man will face court today. (NSW Police) (Supplied)

The women, aged 50 and 34, were charged with a NSW arrest warrant for perjury. The group were remanded in custody to appear at Adelaide Magistrates Court today, where detectives will apply for their extradition to NSW.

Two other men and a woman were also arrested.

A 36-year-old man was charged with four counts of sexual intercourse with a child under 10, 2 counts of indecent assault and having sexual intercourse with a child aged between 10-14. A 48-year-old man was charged with counts of sexual intercourse with a child under 10.

A 45-year-old man in Griffith is accused of sexual intercourse with a child aged under 10. (NSW Police) (Supplied)

A government worker (left) escorts a woman facing court for the child abuse (middle) and her legal representative. (NSW Police) (Supplied)

The woman who have been arrested are facing charges of perjury. (NSW Police) (Supplied)

A 51-year-old woman was charged with perjury.

The investigation dates back to 2012, when detectives from the State Crime Command's Child Abuse and Sex Crimes Squad established Strike Force Hermoyne to investigate allegations of incest, child sexual assault, and serious neglect of children.

The man is also facing charges of indecent assault, sexual intercourse with a child aged between 10 and 14, an aggravated act of indecency and common assault. (NSW Police) (Supplied)

The detectives are specially trained to investigate crimes against children and adults, including sexual assault, serious physical abuse, and extreme cases of neglect.