A Sydney father who shot and killed his two teenage children in their bedrooms in a northern suburbs house on Thursday afternoon may have been planning their deaths, and possibly his own, for more than a year.

Police said John Edwards, 68, in a ‘premeditated and planned’ attack, killed his 15-year-old son Jack and his 13-year-old daughter Jennifer in their Hull Road home at West Pennant Hills about 5.20pm, using two powerful handguns legally obtained earlier this year.

After a massive police operation overnight on Thursday, police found Mr Edwards dead 12 hours later in his Normanhurst home about 4.30am on Friday. 

Police believe the 68-year-old took his own life in his home soon after the shootings. The two guns used to kill his children were found inside his home, located just five kilometres away, where a so-called ‘arsenal’ of firearms was also discovered.

His estranged Russian-born wife Olga Edwards, 36, arrived home from her job of nine years as a solicitor and senior associate at Brown and Partners Solicitors in Woolwich shortly after the shooting.

Ms Edwards graduated from the University of Technology in Sydney in 2008 with a law degree. Photo: Linkedin

Acting Assistant Commissioner Brett McFadden said Ms Edwards was treated for severe shock and was being looked after by friends and police.

“I can’t imagine the significant stress and heartache she is going through,” McFadden said.

He said it was too early to say exactly what happened in the West Pennant Hills house but police believe the killings were “planned and premeditated”.

Mr Edwards had been involved in a custody battle with Ms Edwards for two years following the breakdown of their 16-year marriage.

According to his Linkedin page, Mr Edwards, described as a “recluse” by a neighbour, was a financial planner and volunteered with the NSW Rural Fire Service, Lions Club and Pennant Hills Junior AFL Club.

Neighbours reportedly said Mr Edwards was “very distressed” after his wife and children left.

Juliette Hackett, who lives near Mr Edwards’ home, said she didn’t know the family well but the teenagers “had their challenges”.

“I feel very sad that John felt that there was no alternative than the horrific thing he did,” she said.

Other neighbours reportedly described the extended custody battle as a “real mess”, according to Fairfax Media.

One neighbour, who had known the family for 15 years, said Mr Edwards was “very very distressed” about his wife and children leaving him two years ago, and had spoken about suicide.

“It wouldn’t have surprised me one bit [if he had killed himself],” she told Fairfax.

Another neighbour spoke to Fairfax about an incident in Paris, where he picked up his teenage son by the neck in a restaurant and held him against a wall.

“Poor Jack probably copped the brunt of it … he never had a kind word for those kids, he was very harsh,” the neighbour recounted.

‘There was nothing we could do to help them’

“When ambulance paramedics arrived … we were confronted with an extremely distressing and stressful situation,” NSW Ambulance Inspector Kevin Sweeney told reporters at the scene of the shooting on Thursday.

“Two teenagers were unfortunately deceased in their bedroom and unfortunately at that time there was nothing we could do to help them.”

Mr McFadden said emergency services had arrived to an “horrific scene”.

“It was a very harrowing experience for the emergency services who responded,” he said.

“You’ve got a family that is going to struggle to come to terms with it and emergency responders will struggle to come to terms with what they have seen.”

Meanwhile, Prime Minister Malcolm Turnbull has described the murder of the two teenagers as “heartbreaking” and “shocking”.

“It’s a terrible, terrible tragedy,” the Prime Minister told reporters on Friday.

“Our hearts go out to the mother and to all of the family.

“We mourn the loss of those young people and pray that those who have been so, so hurt by this shocking crime can find comfort in prayer and the consolation from friends and loved ones.”

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