What we know about Sydney double murder

A FATHER HORRIFICALLY MURDERS HIS TWO CHILDREN

WHO WERE THE VICTIMS?

A 15-year-old boy and his 13-year-old sister were shot at the West Pennant Hills home they shared with their 36-year-old mother who was treated for severe shock after arriving at the scene.

The mother, Olga Edwards is a solicitor at Brown and Partners in Woolwich.

WHO WAS THE KILLER?

John Edwards, 68, lived in nearby Normanhurst. Police say the parents' long-term relationship had broken down and a custody battle had been ongoing for about two years.

Mr Edwards, who was 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, according to his LinkedIn page.

HOW WERE THE CHILDREN FOUND?

Neighbours heard gunshots in Hull Rd, a quiet suburban street, about 5.20pm on Thursday and called police and paramedics. Emergency services found the children dead in a bedroom.

WHEN WAS THE FATHER FOUND?

The father's body was found in his home in the early hours of Friday but police believe he took his life shortly after murdering his children.

HOW DID HE ACQUIRE THE MURDER WEAPONS?

He had at least four guns. Police say two "quite powerful" pistols used in the murder and subsequent suicide were acquired legally this year and the murder was premeditated.

WHAT ARE PEOPLE SAYING?

"I feel very sad that John felt that there was no alternative than the horrific thing he did" - neighbour Juliette Hackett.

"It's a terrible tragedy that he thought that was the only option, to take the kids instead of letting them live with their mother" - Normanhurst resident.

"I feel so shocked. Kids are innocent. Whatever the reason, kids shouldn't suffer" - a West Pennant Hills resident.

"The information we've gleaned ... leads me to believe this was premeditated and planned" - NSW Police Acting Assistant Commissioner Brett McFadden.

"The nature of the relationship in recent times and level of access he had to the children ... is subject to the investigation" - Mr McFadden.

"When ambulance paramedics arrived ... we were confronted with an extremely distressing and stressful situation" - NSW Ambulance Inspector Kevin Sweeney.

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