The 53-year-old was found unresponsive about 4.50pm yesterday in a cell at western Sydney's Silverwater Correctional Complex.
Warning: This story contains the name and images of a deceased Indigenous person.
Adrian Torrens was spared jail and was serving a community corrections order for breaching an AVO when he allegedly murdered Central Coast teenager Audrey Griffin, it can now be revealed.
The 53-year-old was found unresponsive about 4.50pm yesterday in a cell at western Sydney's Silverwater Correctional Complex.
Corrective Services personnel and paramedics were unable to revive him.
READ MORE: Hundreds gather in sunset vigil for allegedly murdered NSW teenager
The discovery, which wasn't revealed until later in the night, came during a vigil that was held for the 19-year-old, with hundreds gathering in Terrigal to pay tribute to the vibrant young woman.
Griffin's mother, Kathleen, received a call from police informing her of the news of Torrens' death as she was leaving the vigil.
The news was described as "bittersweet" by her loved ones.
9News can now reveal that Torrens was serving an 18-month community corrections order at the time of Griffin's murder.
Torrens avoided prison when he was sentenced last October for using a carriage service to harass, menace or offend, and for breaching an AVO.
Torrens had a long history of violent offending and breaching restraining orders.
It can also be revealed that Torrens made a confession to someone close to him about Griffin's murder on the phone in the weeks after her death.
"I just f------ clicked and I have no reason for my actions," he said on the call.
"I just did it, man. I was so f----- up, you know?"
In a following call, he apparently admitted to killing someone.
"I killed someone about a month ago, and now they're looking for me," he said.
Earlier this week, Torrens was charged with 11 separate domestic violence offences relating to another victim.
NSW Premier Chris Minns said he was aware of those reports, which he described as "concerning".
"As soon as we have answers, we'll report them to the family," Minns said.
Griffin's death was initially labelled a drowning by police after her partially submerged body was discovered in Erina Creek on the NSW Central Coast on the afternoon of March 24.
After initially not finding any suspicious circumstances surrounding her death, a homicide investigation was launched following a tip-off from the public.
Police sent out an appeal for information last week along with a photo allegedly showing Torrens near Hotel Gosford, around the time Griffin left her friends and began walking towards Terrigal, about 2am.
Authorities were working off the theory that Torrens followed Griffin, whom he didn't know, from the pub before assaulting her and the teen drowned as a result.
Police said Torrens' DNA was found under Griffin's fingernails and that a witness heard a high-pitched scream in the area around 3am.
He was later arrested and charged with Griffin's murder.
The turn of events left her family, friends and community shocked.
Torrens was put through a mental health assessment when he was remanded in custody.
His death is being treated as a suicide.
A coroner will now determine how his death could have happened within Silverwater jail.
Readers seeking support can contact Lifeline on 13 11 14 or beyond blue on 1300 22 4636.
National Sexual Assault, Domestic Family Violence Counselling Service 1800RESPECT (1800 737 732).
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