Shocking evidence of entrenched child sex abuse in regional Aboriginal communities has been uncovered, with more than 30 alleged paedophiles charged after a crackdown in the Pilbara.

It is believed to be among the most arrests from an abuse investigation in regional WA.

The nine-month operation has prompted calls for more intervention in the communities, as well as support for affected children.

The alleged perpetrators have been charged with close to 300 offences, including sexual penetration, and are accused of interfering with children as young as nine.

Most of the accused men are Aboriginal and are from Roebourne, Wickham, Karratha and surrounding areas, with some regarded as leaders in their communities.

Children’s Commissioner Colin Pettit said he was pleased about the “diligent” investigations, which also showed how vital it was to support scared children to speak out, no matter where they lived.

He has asked agencies to ensure the young people involved and their families were given the support they needed to recover from the trauma.

“Once this process is over, it is incredibly important for a strong preventive approach to be established in these communities and maintained for the long term,” Mr Pettit said.

“Every child and young person has the right to live in a caring and nurturing environment and be protected from harm and exploitation.”

Some men are accused of preying on more than one girl and there are allegations the depravity had become so normalised that girls sought out men to sell themselves for cigarettes or alcohol.

Mining magnate Andrew Forrest was criticised when he raised concerns about Roebourne in 2011, claiming “little girls” had approached him in the street and offered him sexual services in exchange for the price of a cigarette.

A group of local indigenous women labelled his comments a racist slur and threatened to refer him to the Human Rights Commission.

Mr Forrest did not want to dwell on that complaint, which was not pursued, but said yesterday he believed the allegations emerging from the Pilbara demonstrated the need for further intervention in remote Aboriginal communities, including cashless debit cards.

“Wherever there is unchecked cash welfare and abuse of alcohol or other substances, and no change in leadership, or failed policies, a directionless community results and tragedies like this can happen,” Mr Forrest said.

It is understood the investigation started in September after police gained the confidence of an injured girl who had sought treatment at hospital.

Police spent a lot of time in the communities earning the trust of children and their families to uncover incidents.

The accused perpetrators range from teenagers to men in their 70s. It is understood a recovery group led by the Department for Child Protection has been set up as part of a State Government response.

Wherever there is unchecked cash welfare and abuse of alcohol or other substances, and no change in leadership, or failed policies, a directionless community results and tragedies like this can happen.

Special counselling services are being provided and dedicated child protection workers have been appointed to ensure the affected children are safe.

Communities in the Kimberley and Mid West have previously been the focus of similar police inquiries amid suspected under-reporting of child sex abuse.

WA child protection expert Andrea Musulin, director of the Perth Catholic Archdiocese’s Safeguarding Services program and a former police officer, said the alleged abuse highlighted the importance of teaching children how to protect themselves.

“Even though it is the adults’ responsibility to protect children ... by educating children we may be able to prevent some offences happening or at least empower them to report abuse,” she said.

The sooner children disclosed offences and received support, the better chance they had of recovering from the trauma and the less likely they were to go on to become abusers themselves, she said.

Anyone who would like to seek advice or support can contact Crisis Care on 1800 199 008 or Lifeline 13 11 14