Sydney Father Spent Year Planning Murder Of Son And Daughter

John Edwards' brutal attack on his kids was meticulously planned.

A father who gunned down his two children in Sydney's north-west may have spent a year planning the murder and hired a car on the day so his son and daughter wouldn't recognise him.

John Edwards, 68, reportedly timed the callous take-down just before the end of school term when he knew the siblings would be alone and before their mother, Olga Edwards, got back from work.

Edwards, who later took his own life at a nearby Normanhurst property, also left a series of letters to be read by the family after his death, according to The Daily Telegraph.

Jack and Jennifer Edwards were shot by their father at their West Pennant Hills home. Image: Supplied

The horrific murders of Edwards' son, 15, and daughter, 13, took place at their Pennant Hills home on Thursday in what police have described as a domestic violence related incident.

It has since been revealed by The Sun Herald that the murdered children were part of Edwards' second family. It is believed Edwards had two children in the 1980s to his first wife, from whom he separated in 2000 or 2001.

It has been reported that Edwards had no continuing relationship with his first family -- including a son and daughter, despite the fact they lived in the same area on Sydney's north shore.

Police have said that Edwards used firearms registered in his name in the attack.

“The 68-year-old male was the holder of a number of firearms,” NSW Police Acting Region Commander Brett McFadden told reporters on Friday.

“We understand that those handguns came into his possession lawfully earlier this year.

“The information we’ve gleaned … leads me to believe this was premeditated and planned.”

While police are still piecing together what could have driven Edwards to kill his teenage children they have said the parents' long-term relationship had broken down and a custody battle had been ongoing for about two years.

Edwards has been described by neighbours as a reclusive and anti-social person who lived alone after the breakup of his relationship with the children's mother.

“I reckon I had two conversations with him in almost 20 years,” one neighbor told the Guardian.

“I’ve seen that photo of him in the media where he’s smiling. I don’t think I ever saw him smile.”

The self-employed financial planner, who volunteered with a number of local groups, was also reportedly turned away from a number of gun clubs in the years leading up to the double murder.

Police have offered support services to family members, the wider community and emergency personnel in the wake of the tragedy.

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