A Sydney man whose remains were found in the Royal National Park north of Wollongong last year may have been murdered.
Police confirmed on Tuesday they were treating the death of Lynn Tasman Jones as suspicious.
A bushwalker discovered Mr Jones's skeletal remains in bushland on Lady Wakehurst Drive near Otford on October 7 last year, prompting a major police and State Emergency Service search of the site.
Mr Jones was 69 when he was last seen in his home suburb of Waverley about 6.30pm on Wednesday, June 10, 2009.
His white 1991 Toyota Camry wagon - with NSW registration AQ-72-UY - was reportedly seen parked on Windmill Street, Millers Point, about 10am the following day.
The vehicle has never been recovered by police.
Speaking to the Mercury on Tuesday, officer in charge of the investigation Detective Sergeant Michael Todd said police were pursuing several "lines of inquiry" into Mr Jones's death.
However, he said police had received limited information from the community, and called on anyone who saw suspicious activity around Otford at the time of Mr Jones's disappearance to contact Crime Stoppers.
Mr Jones's remains were discovered just metres from the roadside near a creek.
"We haven't had too much feedback from the community at all unfortunately," Det Sgt Todd said.
"Most of the activity happened in the Sydney area rather than the Wollongong area."
Det Sgt Todd said the circumstances surrounding the disappearance of Mr Jones had led them to treat his death as suspicious.
However, he would not go into detail about the circumstances or the lines of inquiry police were pursuing.
Det Sgt Todd said Mr Jones had few surviving family members, except for a half sister.
Detectives have appealed for anyone who may have seen his Toyota Camry on June 11, 2009, or has any information that could assist police to call Crime Stoppers on 1800 333 000.