"I've lost my boy because they didn't do their job out there," she said. "He should never have gone back there after what happened to him." A police spokesman said it received reports of a dead man inside a cell around 11.30am. The force has also confirmed the death will be investigated by its criminal investigations detectives. In April last year, Freeman was found unconscious and critically injured in his cell within several hours of his arrival at the Alexander Maconochie Centre. Prison officers resuscitated Freeman before he was placed in an induced coma in hospital for a week, with fears he could suffer a lasting brain injury. The attack happened just hours after he was remanded in custody on charges of disqualified and drink-driving, riding in a stolen car, possessing an offensive weapon with intent, and escaping arrest.

In May, Freeman was sent back to jail despite warnings that he may be killed by other inmates and evidence of self-harm risks. At Freeman's bail hearing in the ACT Magistrates Court, Ms King said she had received a phone call warning her son would die if he went back to the AMC. "I'm very fearful for my son's safety because I know he's not going to be walking out of there," she said. But police described the prison as the "safest place" for Freeman and prison staff told the court extra precautions had been taken to ensure his safety. Aboriginal Legal Service lawyer Dean Rutherford told the court Freeman may be killed if he was sent back to prison, and the risk of him reoffending could be managed by an effective home detention and other strict bail conditions.

On Friday, Ms King said authorities had failed to protect her son. "My son was never a violent man. He just stole a few cars," she said. Julie Tongs, a senior Aboriginal health official who called for an independent inquiry into the bashing of Freeman last year, said the news was devastating. "It's reconciliation week," she said. "Earlier today we had a march across Commonwealth Bridge with 3000 people showing their support, so to get this news now is just heartbreaking." Ms Tongs, chief executive of Winnunga Nimmityjah, said Freeman's death could have been avoided if a full scale inquiry was launched.

"This man's circumstances should have been very different; he should have been able to live a long and healthy life," she said. "It is not easy when you bury your children and for some of the mothers in our community, it just doesn't end." Correction Minister Shane Rattenbury described the death as a tragedy and of the deepest concern. "On behalf of the ACT government, I would like to express my deepest sympathy to the family and friends of the individual," he said. "There are particular sensitivities surrounding the individual and, as such, I will be launching an independent inquiry into the circumstances surrounding the care and supervision of the detainee during their period of incarceration.

"I am advised that the discovery was made when Corrective Services staff were notified by a detainee that they were concerned about the health of another detainee. I am further advised that no disturbances were reported around the time of the incident."