THE two children executed by their father "in a premeditated and planned" attack inside their suburban Sydney home have been identified.
Financial planner John Edwards, 68, is believed to have entered his estranged wife's house on Hull Rd in West Pennant Hills and shot dead their teen son and daughter in a bedroom, about 5.30pm on Thursday. The slain victims have been identified as Jack, 15, and Jennifer Edwards, 13.
He timed the chilling attack just before the end of school term when he knew they would be alone and before their mother, Olga Edwards, returned home from work.
Ms Edwards, 36, arrived home soon after to the "horrific scene" and collapsed from "severe shock", about 6.30pm.
Ms Edwards, a solicitor, was understood to be in the care of friends on Friday.
Police said the murders were "targeted" and related to domestic violence and came amid a two-year custody battle between Mr Edwards and his wife.
Edwards has been described as a loner, who was anti-social and abusive to his children.
The gunman's body was found in a Normanhurst home, about 5km from the scene of the initial killings, about 12 hours after his children were found dead.
NSW Police Acting Region Commander Brett McFadden told reporters the couple had been in a long-term relationship.
However, that had broken down in recent years and Edwards lived separately from the rest of the family at the Normanhurst address where he died.
Edwards - who described himself online as a "certified financial planner" - had owned the Normanhurst house since 2014.
News.com.au understands Edwards was self-employed and had been aligned with AMP from 1995 until 2016.
"37 years of experience as a self-employed businessman," Edwards wrote in his LinkedIn bio.
His mother told The Daily Telegraph he "became reclusive" and "just kept to himself" after he retired and the family separated.
On social media, Edwards listed himself as a volunteer for the NSW Rural Fire Service and Lions Club International. News.com.au has contacted both organisations but spokespersons said they were unable to yet deny or verify the alleged affiliations.
Jack was a student at Pennant Hills High School. His classmates were informed of his tragic death in an assembly earlier today.
A spokesperson for the school referred news.com.au to the NSW Department of Education which declined to comment further. Jennifer attended a selective school, according to The Guardian.
The teenagers had been at home by themselves in the moments leading up to their deaths, according to police.
Two "quite powerful" pistols used in the shootings - and another two guns - were later recovered from the Normanhurst property.
"The 68-year-old male was the holder of a number of firearms," Supt McFadden told reporters in Sydney on Friday.
"The two handguns were registered in his name.
"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."
Edwards was previously known to police but his criminal record was from "many years ago" and not "extensive", according to Supt McFadden.
"The details about the nature of the relationship, particularly in recent times, and the level of access that the 68-year-old had to his children is subject to investigation," Supt McFadden said.
"I do know there were some custody hearings over the last two years.
"This was a planned activity on the part of the 68-year-old male and we are of the belief that shortly thereafter he has attended the address at Normanhurst and taken his own life.
"It's too early to get a full appreciation of what went on in the (West Pennant Hills) premises."
Earlier, Supt McFadden told news.com.au it had not yet been determined how many shots were fired but that police were speaking with several witnesses.
He told reporters the attack was a "very harrowing experience for those initial responding emergency service providers" who were called to the "horrific scene" following reports of gunshots.
"It is what can only be described as a tragic set of circumstances for the whole family," Supt McFadden said.
NSW Ambulance Inspector Kevin McSweeney said that when paramedics arrived they "were confronted with an extremely distressing and stressful situation".
"Two teenagers were unfortunately deceased in their bedroom and unfortunately at that time there was nothing we could do to help them," he said.
At the scene of the bloody attack on Thursday evening, forensic investigators wearing white protective suits could be seen walking up and down the street with torches and cameras.
About 150m of the road was blocked off, with witches hats stopping cars from entering one end, and uniformed police officers standing guard on both.
Some residents who lived in the exclusion zone were escorted back inside their houses upon arriving late to the horror that, on this occasion, had come too close to home. It's understood the two teens' bodies were removed just before 6am the following day.
Longtime resident John Howard, 82, told news.com.au it was "normally a pretty quiet street".
Mr Howard said he didn't hear any gunshots. He was alerted to the incident when his daughter saw it on the news and contacted him before he came outside.
"I couldn't believe it," he said. "It's so horrific … especially for such young people to be the ones killed."
Prime Minister Malcolm Turnbull described the killings as "a terrible, terrible tragedy".
"Our hearts go out to the mother and to all of the family," he said.
"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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