Former Rebels bikie gang enforcer Ricky Ciano died from a drug overdose but how that deadly hit got into his system is a mystery.
As police released footage on Thursday of the last time the 35-year-old was seen alive, detectives also confirmed they were investigating whether he was killed by a "hot shot" - a lethal hit of drugs administered by someone else.
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Police release footage of ex-bikie's last known moments
Police continue to investigate how ex-Rebels gang figure Ricky Ciano turned up dead in Oberon, NSW.
Mr Ciano's body, stripped down to only his underwear and shoes or socks, was found sprawled on the back seat of his BMW M3 on the outskirts of Oberon in the NSW Central Tablelands in February.
The former president of the Rebels' Sydney chapter, who left the gang in 2015, had been living in Queensland just before his death.
![Images of Ricky Ciano's car travelling through the western outskirts of Sydney days before he was found dead.](http://web.archive.org./web/20170714170928im_/https://www.fairfaxstatic.com.au/content/dam/images/g/x/9/z/z/x/image.related.articleLeadwide.620x349.gx9ydw.png/1499952015406.jpg)
He flew into Sydney from the Gold Coast on the morning of February 11 before picking up his BMW at airport parking.
He told friends and family he was going to visit his daughter.
He then drove towards Penrith to visit friends.
He was pulled over by Traffic and Highway Patrol in the Penrith area at 11.40am.
![The crime scene outside Oberon in the Central Tablelands where the body was found.](http://web.archive.org./web/20170714170928im_/https://www.fairfaxstatic.com.au/content/dam/images/g/u/d/q/w/o/image.related.articleLeadwide.620x349.gx9ydw.png/1499952015406.jpg)
But he was captured on a road toll camera driving his BMW towards Oberon on the afternoon of February 11.
The singlet he was wearing and tattoos on his right arm are clearly visible.
![Ricky Ciano was allegedly targeted for murder at his Central Coast home in 2015.](http://web.archive.org./web/20170714170928im_/https://www.fairfaxstatic.com.au/content/dam/images/g/t/g/a/0/5/image.related.articleLeadwide.620x349.gx9ydw.png/1499952015406.jpg)
His car turned up in the Oberon area that weekend, for reasons homicide detectives still do not know.
Mr Ciano's body was found in his car, parked just off Duckmaloi Road, on February 14.
![Former Rebels bikie gang member Ricky Ciano was last seen alive in Penrith in Sydney's west on February 11.](http://web.archive.org./web/20170714170928im_/https://www.fairfaxstatic.com.au/content/dam/images/g/u/c/v/7/r/image.related.articleLeadNarrow.300x0.gx9ydw.png/1499952015406.jpg)
He had been stripped of his clothes, which have not been found.
"We have Oberon as just a complete mystery to us at the moment as to what he is doing up there and who he is with," Homicide Squad Detective acting Superintendent Jason Dickinson told reporters on Thursday.
"That's part of the appeal today. We are really keen for people to come forward and put some context around that for us."
Acting Superintendent Dickinson confirmed the cause of Mr Ciano's death was a drug overdose but said investigators were keeping an open mind as to how those drugs ended up in his system.
"Information from those that know Mr Ciano well indicates that he had previously used drugs," he said.
"Certainly what we have seen surrounding the circumstances of his death is out of character.
"The issue of what is in his system is one issue. What we are interested in is how that came to be in his system."
Adding to the mystery was the discovery of a syringe in Mr Ciano's car.
Police on Thursday released footage from the video inside the highway patrol car in the hope someone might recall having seen Mr Ciano that weekend.
Mr Ciano told his wife he had to leave his car by the side of the road and walk the rest of the way to his friend's house at Penrith.
However this is at odds with his car being spotted driving towards Oberon later that afternoon.
His wife, who lives on the Gold Coast, last heard from him in a text message at 8.20pm on February 11. Mr Ciano told her there was a blackout and he was unable to charge his phone, a friend told Fairfax Media in February.
Acting Superintendent Dickinson said Mr Ciano's car travelled back and forth between Oberon and the Blue Mountains but someone else may have been driving it.
Police believe Mr Ciano's body may have been in his car as early as the next afternoon, Sunday, February 12.
He was reported missing the next day.
Mr Ciano had been the target of a $500,000 kill contract in 2015.
Rebels figure Abuzar Sultani allegedly turned up at the front door of his Central Coast home under the guise of delivering pizza but Mr Ciano refused to open the door.
Mr Ciano later moved to the Gold Coast to be closer to his family and for a lifestyle change, friends say.
Acting Superintendent Dickinson said there was no information linking Mr Ciano's death to any other offence.
Anyone with information can call Crime Stoppers on 1800 000 333.