A man has been convicted of what prosecutors have described as the “cold-blooded” murder of a previously convicted killer. Eric James Forrest was found guilty of the crime and will undergo sentencing procedures in February.

Forrest’s victim, whose name has not been disclosed, was previously convicted of murder. He had been sentenced to 20 years in prison for the 2000 killing of a teenager during a failed robbery in Sydney’s north shore.

The tragic events of 2000 unfolded as Shahab Kargarian and his girlfriend enjoyed their takeaway meal in a park. It was then that the convicted killer, accompanied by an accomplice, confronted the 17-year-old, demanding his wallet.

In the ensuing chaos, the assailant fired four to five shots at Shahab, resulting in the teenager’s death during the botched robbery.

During Forrest’s trial, it was revealed that in his final moments on a property in Mudgee, the victim pleaded with Forrest, appealing to his sense of humanity in a bid to save his own life.

Forrest’s trial was told when faced with death on the Mudgee property, Collisson made a desperate appeal to his killer’s humanity.

Prosecutors told jurors the victim drove to the country a day earlier to collect goods to sell, but was killed after 9.12pm the next night on a secluded hill.

Forrest pulled out a sawn-off shotgun and pointed it at Collisson, saying forcefully “you want to treat me like a gronk”.

“The Crown case is that the accused was angry about something – precisely what is not known,” crown prosecutor Emma Blizard told the jury in early October.

She said Collisson pleaded with the younger man, telling him “please don’t, I’ve got kids” and “I love you Eric, like, you’re my brother” before he was shot in the neck or shoulder.

He tried to run away, but Forrest reloaded the gun and shot him twice more, Blizard said.

Collisson’s body was moved into a large hollow tree stump and burned, the jury heard.

Bone fragments – including 17 teeth – were found inside the tree.

Forrest’s lawyer cast doubt on the prosecution witnesses’ evidence, saying they had used ice, which could have affected what they were able to tell the court.

One eyewitness had also received a reduction in his sentence for criminal matters in exchange for his assistance with the three-week trial, Justine Hopper said.

Jurors spent almost a week deliberating before returning a guilty verdict to murder about 11.25am today.

In November 2023, the then-homicide commander of NSW Police said Collisson had been killed in cold blood in a brutal fashion.

“You can only call it callous and cold-blooded, the way he’s been killed,” Detective Superintendent Danny Doherty said.

Forrest will return to court on February 27 for sentencing submissions and will be sentenced at a later date.