A man jailed for two decades for the murder of a teenager in a bungled robbery attempt has been declared missing after his release in a potential homicide case.
David Collisson, 53, was reported missing on October 15 after he was last seen at a property in Menah, northwest of Mudgee in NSW.
NSW Homicide Squad detectives have launched a search of the rural property with the help of police divers and dogs as part of their investigation.
Local police referred the case to homicide investigators after Collisson could not be located or contacted.
His suspicious disappearance comes more than two decades after he was convicted of the "cold blooded, callous and cruel shooting" of 17-year-old Shahab Kargarian.
Shahab and his girlfriend, Shabnam Faiz, 17, were eating takeaway in a park on Sydney's north shore in 2000 when Collisson, accompanied by another man, demanded the teen's wallet.
Collisson then shot the victim four to five times in a robbery gone wrong.
His sentencing judge, Justice Tony Whealy, said the killer was "determined to end this young man's life and kept firing until he had achieved his object".
"He ... has simply failed to face up to and take responsibility for his actions," Justice Whealy said.
Collisson pleaded not guilty to the murder and maintained his innocence throughout the trial and sentencing.
A former able seaman, Collisson worked as a general manager at a car dealership prior to Shahab's murder.
He was sentenced to a minimum of 18 years in prison and released on parole in November 2018.
His parole was revoked in September 2020 for outstanding charges of driving offences which were later dismissed.
Collisson was again sentenced to nine months imprisonment for causing bodily harm, with his sentence expiring in June 2021.
He remained in custody until his release in April 2022 to serve the balance of his parole but it was revoked on October 13 this year after he failed to report to his community corrections officer, the state parole board said.
His parole is set to expire in October 2024.
Police urged anyone with knowledge of Collisson's whereabouts to contact Crime Stoppers.
