Vulnerable disabled children at three private care homes in Doncaster faced serious bullying, physical abuse and sexual harm, a review has found.
The children were controlled by using dangerous physical restraints or were locked up in solitary confinement.
The Child Safeguarding Practice Review Panel examined the experiences of 108 children and young adults living at Fullerton House, Wilsic Hall and Wheatley House between January 2018 to March 2021.
There was also evidence of sexual harm, medication being misused and maladministered to the youngsters, many of whom didn't or couldn't speak because of autism.
The review, which was launched in January, found a number of complaints had been made to Ofsted dating back to 2015.
All three homes have now been closed down following a police investigation.
The panel is now demanding urgent action from councils across the country and Ofsted to ensure similar children's homes are safe.
Report author, Susan Tranter, said: "We were very shocked and alarmed by the scale of the abuse that was perpetrated against these very vulnerable children.
"As part of this review, we have some urgent actions we've asked all directors of children's services to make.
"We've asked them to undertake a quality and safety review to make sure that the child is safe, well, their needs are being met, and the conditions are right for them to thrive."
Hesley Group, who operated the residential special schools, said it took “swift action” to address concerns at the time, including dismissing several staff, and deregistered the homes.
A spokesperson said: "We are deeply sorry for the hurt caused to young people and their families over this period.
"We have since undergone a major restructure and made significant changes across our senior management team."
"We will carefully consider the issues raised in the National Child Safeguarding Practice Review Panel’s initial report to make sure improvements can continue to be made."
A separate investigation - Operation Lemur Alpha - is being carried out by the Doncaster Safeguarding Children Partnership and includes a criminal investigation by South Yorkshire Police.
Detective Chief Inspector, Phil Etheridge, who is leading the investigation said the investigation also involves offences against some young adults.
"Our findings to this date are that we’ve uncovered a number of offences relating to child abuse, particularly around assaults, neglect, misadministration of medicines etc, those are the early finding from within our criminal investigation."
Ofsted said "It is clear that the management and staff of these homes were not open and honest with authorities, including Ofsted. But it's also clear there are lessons for all of us to learn."
A second phase of the review seeking to identify necessary changes is expected to be published in spring 2023.
In the meantime, Doncaster Council will work with other authorities to support the victims in their recovery.
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