Please note: This story contains reference to someone who has died.

An Indigenous man from Port Lincoln died in custody at Royal Adelaide Hospital (RAH) on Thursday.

The 37-year-old was taken to RAH last month and passed away whilst on remand in the hospital's mental health ward.

The South Australian Aboriginal Legal Rights Movement is supporting the family in seeking justice.

Speaking to NITV, Aboriginal Legal Rights Movement CEO Chris Larkin said the organisation will "provide the family with any support they need" to support them through this "tragedy".

Larkin also criticised the Government's lack of action in implementing the recommendations of the 1991 Royal Commission into Aboriginal Deaths in Custody.

"For years we've been talking about the recommendations of the Royal Commission ... they haven't happened," he said.

"What we need to do is not only put in place those recommendations, but we need to actually put in place programs which prevent people going into custody or coming into contact with the justice system."

Circumstances around the death in custody are currently being investigated by the South Australian Department of Correctional Services.

"The Department is working with the family and will offer ongoing support during this difficult time. The incident has been referred to the Coroner's Office," the Department said in a statement.

Thursday saw two Indigenous deaths in custody, the 37-year-old man at RAH and a 43-year-old man in New South Wales.

The 43-year-old Ngemba man was found unresponsive in his cell at Long Bay Correctional Complex in Sydney on Thursday morning.

Since March 2021, 10 Indigenous people have died in custody and there have been almost 500 deaths since the 1991 Royal Commission into Aboriginal Deaths in Custody.

According to the Victorian Aboriginal Legal Service, on average there has been one Indigenous death in custody every three weeks since the Royal Commission.

It has been 30 years since the Royal Commission into Aboriginal Deaths in Custody made 339 recommendations to help end Aboriginal deaths in custody.#BlackLivesMatter #StopBlackDeathsinCustody #RCIADIC #springst #auspol pic.twitter.com/fAnWpd4jed

â€" VALS (@thevalsmob) July 14, 2021

By Rachael Knowles