A father probably killed his son with a steak knife, uttered Allah's name and dropped the three-year-old down a disused mine shaft, the South Australian Supreme Court has been told
Prosecutors in the case involving Aliya Zilic said that he had taken the boy, Imran, 3½, from his mother's Perth home a few days earlier.
Mr Zilic is on trial accused of murdering his only son during an access visit in April 2008.
He has pleaded not guilty by reason of mental incompetence.
Horrific details of the youngster's final moments emerged in the court, with prosecutor Jim Pearce saying it was likely Mr Zilic had killed his son with a steak knife before dropping him down the 7m disused shaft.
Mr Pearce said the accused had told police: 'I killed him, does it matter how?' and 'I said Allah's name and dropped him in the shaft'.
The court was told Mr Zilic had an extensive history of mental health problems and psychiatrists would be called to give evidence about his mental competency at the time of the alleged murder.
During his relationship with Mirsada Halilovic he had allegedly "used and abused" amphetamines and cannabis. The couple eventually separated because Mr Zilic was domineering, abusive and had been physically violent, the court was told.
Mr Pearce said he accused Ms Halilovic of being a whore who was possessed by demons and was working for the devil.
Ms Halilovic allowed her ex-husband to see his son, although she did not like Mr Zilic to take him for overnight visits.
Mr Zilic allegedly arrived at her Koondoola home unannounced about 6am on Sunday, April 20, 2008.
He told his ex-wife he missed his son and wanted to take him to stay at his brother's for a few days. The court was told he quickly rushed out without taking any clothes for the youngster.
It would be the last time Ms Halilovic saw her son alive.
Mr Pearce told the court Mr Zilic had then left Perth and headed to the South Australian town of Coober Pedy, 800km north of Adelaide, where he had been renting a unit.
There were sightings of the pair at businesses across WA and SA.
Ms Halilovic repeatedly tried to call her ex-husband that day and the next and found out his brother had not seen him.
He eventually answered his phone on the evening of April 21 and she spoke briefly to her son. But it will be alleged she called police when his father did not return him as promised the next day.
Prosecutors allege Mr Zilic killed his son on April 22 or 23, soon after arriving in Coober Pedy. The court was told he then left South Australia and headed to WA, to the north-west town of Kununurra.
Police searching for Imran questioned Mr Zilic in Kununurra. The court heard he initially told them he had taken his son back to his ex-wife but, after several interviews with detectives, he eventually admitted killing Imran and described where he had left his body.
He allegedly told police he left the child “in the hands of God”.
“He described how he thought Imran was the devil’s helper and he now thought that Imran was at peace with God,” the prosecutor said.
The trial is being held in South Australia because that is where Imran was found.
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