A six-year-old schoolgirl was stripped and sexually abused by almost two dozen classmates on a daily basis, it was revealed today.
The child was subjected to the horrific ordeal within the grounds of her primary school by 23 classmates her own age for months.
An official inquiry into the abuse the child regularly suffered accepted that sexually harmful behaviour did take place.
But it concluded that no action could be taken against those responsible because they were too young.
The youth of the children made it impossible to gather proof of what had happened and all were under the age of criminality.
The conclusions of the serious case review were published two years after the allegations were first made.
A review of that inquiry process itself is now under way.
The unnamed schoolgirl is from Wales but neither the school she attended nor the local authority can be identified.
The child has since been moved to a new school but her mother claims she will be scarred for life by the abuse she suffered.
Keith Towler, Children's Commissioner for Wales, called the review "a shocking failure".
"The bottom line is the family will never know what happened to their child," he said.
He also acknowledged that the serious case review system was "failing some of the most vulnerable children".
The mother of the child said it is wrong that nobody will be held accountable for what happened.
The serious case review was only launched by the local authority when she took legal action.
The girl's mother spoke today of her shock and horror at learning from her daughter about the abuse she suffered.
In an interview with BBC Wales, she said: "She was telling me things that I think every mother dreads to hear from their daughter. It was horrendous what she'd gone through.
"Every day she was being stripped. Every day she was being sexually and physically abused and every day she cried out for help and nobody ever came."
She added: "I think that you cannot excuse that. How can you possibly say that that is okay and nobody is answerable for that?"
Mr Towler said a review of the serious case review system was now under way.
"Clearly there are issues with the serious case review system and there is consensus that the current serious case review arrangements are not working effectively," he said today.
"The Welsh government has heard those calls for change and is responding. I will not yet be undertaking a review but instead will be working with practitioners and other relevant officials on two groups which the deputy minister for social services has convened.
"The establishment of the Welsh Safeguarding Forum, of which I'm a member, aims to ensure that safeguarding is achieved at a national, regional and local level.
"This Forum's work is critical in ensuring the system is strengthened and that joint working is improved to safeguard our children.
"Other work is under way with a working group to draft a new framework for undertaking reviews and one of my senior managers is a member of that group.
"This Forum and the Advisory Group must address the ineffective system which will result in change in practice. We cannot find ourselves in the same position again where the system is failing some of our most vulnerable children."Reuse content