Inquest ordered after man dies in WA jail

The death of a 31-year-old man at a maximum-security prison in Western Australia has been referred to the state's coroner.

The Department of Corrective Services has confirmed the Aboriginal man was found unresponsive during a routine check by officers at Casuarina Prison at 9.30pm (WST) on Wednesday.

Prison officers immediately carried out CPR and ambulance officers also examined the man but were unable to revive him.

Commissioner James McMahon described the loss as "tragic" and said the department had a duty of care to protect prisoners and offenders from harm or injury.

"I offer my sincere condolences to the man's family and friends in their grief," he said.

"I also recognise the significant distress this will have on the dedicated staff at Casuarina Prison and across the corrective services system, and in the wider Aboriginal community."

All deaths in custody are subject to a coronial inquest to determine the circumstances and cause of death.

Corrective Services Minister Joe Francis told a march in Perth against deaths in custody that it was believed the man had taken his own life.

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