Terrible loss ... The family of murdered Deer Park post office operator Dzung Nguyen leave the Supreme Court. Credit:Paul Rovere The murder — which was captured on CCTV footage — took place soon after Barbour peered up at a security camera outside the premises and waved to the camera. The vision shows he waited until all other staff had left for the day before he approached the business's rear door and was let inside by Mr Nguyen. Supreme Court Justice Cameron Macaulay said Barbour had been in discussions with Mr Nguyen and his wife earlier about setting up an account with them. They were supplying him cigarettes for his milk bar business. But the couple refused to set up a credit account when he could not pay the full amount he owed them.

Suddenly camera shy ...Riad Barbour is taken into custody in 2008. Credit:Paul Rovere The vision shows Barbour bashing Mr Nguyen several times over the head with a wooden truncheon while he was bending down. "An intense struggle then followed," Justice Macaulay said. "It lasted a number of minutes. Variously, over that time, you hit Mr Nguyen with the truncheon, punched him, struck him with a stapler you grabbed off the office bench, held him in a headlock and, finally, produced a knife and stabbed him a number of times, first to the body and then to the neck." Some of the stab wounds were 20 centimetres deep, the court heard. The judge described the vision as "chilling" and the crime as an act of "savagery".

"(Mr Nguyen's) experience of terror and physical pain does not bear imagination," he added. He said Barbour's explanation of what happened — that he killed Mr Nguyen after he was provoked by a spontaneous perception of danger, that he was bending down to grab a weapon — completely contradicts the CCTV evidence. "The recording shows the two of you engaging in a seemingly comfortable exchange, completely devoid of any appearance of tension or friction," he said. "Mr Nguyen is going back and forth to items on the bench reaching down to boxes on the floor, many times. For quite some time before you began striking him, you adopted a relaxed pose, leaning with your elbow on the safe near the door, and your action to remove your truncheon was slow, deliberate and calculated, waiting for the moment when Mr Nguyen was unguarded in front of you." After killing Mr Nguyen, Barbour helped himself to the post office safe, stealing more than $12,000.

When he was arrested at his Bacchus Marsh home two days later, he had spent the money on gambling and buying drugs. Barbour pleaded guilty to murder and theft. The judge took into account his early guilty plea, remorse and and acceptance of responsibility, and his difficult background in sentencing him today to a minimum of 19-and-a-half-years jail. The court heard he had been a victim of violence at the hands of his alcoholic father, and had witnessed a fellow Syrian soldier being shot and killed on patrol. He was also shot and injured in the back and leg while he was undertaking national service and was likely to be suffering from post traumatic stress. He had been under considerable stress as a result of his failing milk bar business at the time, his inability to repay a large debt to a cousin, and to provide for his family.

He resorted to abusing amphetamines and steroids, withdrew from his family, stopped working in the business, engaged in drug-dealing and gambling. Justice Macaulay accepted that Barbour was "generally at a very low ebb, with feelings of paranoia, anger and aggression exacerbated by the effect of the drugs you were taking" at the time of the murder. But he said the impact of his crime on the family of Mr Nguyen had been, and would continue to be, "absolutely devastating". The judge sentenced the father of two was sentenced to 22 years' jail for the murder and two years' jail for theft, one year of which is to be served concurrently with the murder sentence. The maximum penalty for murder is life, while the maximum penalty for theft is 10 years.

Barbour showed no response upon hearing his fate and kept his head bowed for the duration of the sentence.