CALGARY -- Alberta's police watchdog has been called to investigate after a boy with autism suffered a fractured skull while in the care of Calgary officers.

The Alberta Serious Incident Response Team says the 12-year-old was injured on Wednesday.

Investigators say Calgary police responded to an emergency call about an uncontrollable youth who was causing damage to a home.

Police determined the boy may have been off his medication for days and had been locked in a bedroom.

Investigators say when the officers tried to take him to hospital he struggled and injured his head.

Paramedics were then called and he was taken to hospital.

"At the time, the youth was struggling with officers, was not handcuffed and had not yet been placed in the police vehicle," investigators said Friday in a release.

"EMS was contacted and transported the youth to hospital, where the boy's parents were advised that he had suffered a fracture to his skull."

Investigators declined to release further information.

The Calgary Police Service says it takes in-custody injuries seriously, especially when they involve a minor.

The service says it completely supports the independent investigation and will co-operate fully.

The police service says its officers are trained to resolve situations with as little risk as possible to themselves, the public and the people it takes into custody.

"Our officers also do the best they can in situations where people are often unpredictable and combative," Calgary police said in release.

"In this case, the boy was taken into custody for transport to the hospital and was not co-operative.

"This incident did not have the outcome that anyone involved wanted, and anything that can be learned through the investigation to prevent similar incidents in the future will be valuable."

The Alberta Serious Incident Response Team reports to the province's Justice Department.

The team's mandate is to investigate when the actions of Alberta's police result in serious injury or death to any person, as well as serious or sensitive allegations of police misconduct.