NSW police are investigating allegations a child with autism was disciplined by being locked in a dark cupboard at a Newcastle school.
The boy's father, David Roy, raised the allegations of abuse against his seven-year-old son at Kotara South Public School.
Mr Roy said his son, who is now home-schooled, was traumatised.
"It's suggested that he was locked in a darkened cupboard with heavy objects around him," he said.
"He is indicating to us that he was grabbed and hit."
Mr Roy said his son shuts down when remembering the alleged abuse.
He said he has told police he is worried there were child protection breaches against his son.
"He speaks after he's passed by where the incidents happened, if we have to drive past there, and within an hour he will regress into himself and shut down," Mr Roy said.
The ABC has obtained a medical report of one incident, where doctors say bruising to Mr Roy's son was consistent with finger marks.
The Education Department said it was investigating, but said it was not appropriate to comment on departmental or police investigations.
'System in crisis'
The boy's case comes a day after the ABC revealed nearly 40 incidents of New South Wales teachers being investigated for abusing children with autism.
Children with Disability Australia chief executive Stephanie Gotlib said a royal commission was needed to shine the light on the issue.
"I was shocked by the list that was provided through that FOI [Freedom of Information] request but clearly, clearly we must do something about this," she said.
"This information again highlights that we have a system that is in critical need of reform.
"The increasing occurrence and reporting of these incidents are absolutely reflective of a system in crisis.
"It is not okay to do this stuff, it is not okay to bonk a kid on the head with a book, it is not okay to drag them and tackle them to the ground.
"It is not acceptable."