In 1996, a gunman opened fire at a tourist attraction in the town of Port Arthur, killing 35 people and wounding 22 others.
Of the seven people found at the house, five were discovered inside a converted shed, while two were found outside. They found three generations of the same family killed and recovered two firearms from the scene.
The bodies of seven people, including 4 autistic children, were found near or at a farm property in Osmington near the South-western tip of Australia, confirmed Western Australia State Police Commissioner Chris Dawson.
He would not confirm reports that police suspected that Mr Miles, Katrina's father and the grandfather of the four children, had called police at 5.15am on Friday, shortly before his and his six relatives' bodies were found.
Arrived at the scene the police found in the private possession of the 7 human bodies with traces of gunshot wounds.
"This devastating tragedy will no doubt have a lasting impact on the families concerned, the whole community and in particular, the local communities in our South West", Dawson said. While some in the US have argued in favor of gun regulations similar to those of Australia, others have argued America's situation is different, indicating alternative solutions are necessary to prevent mass shootings in the U.S.
The police commissioner said homicide detectives were helping local police with the investigation, supported by specialist units and a chaplain.
The crime scene is so extensive, senior WA police expect to be at the site for up to five days.
Commissioner Dawson said the small Osmington community would be reeling but was confident it would rally together.
'Two firearms have been located at the scene.
"When Australia had a mass killing-I think it was in Tasmania-about 25 years ago, it was just so shocking the entire country said, 'Well, we're going to completely change our gun laws, ' and they did", he told comedian Marc Maron during a podcast taping.
Locals have been left struggling to understand how their tight community could be ripped apart by the massacre of a family of seven, including four young children aged between eight and 13.
News.com.au has seen a social media post from someone who knew the family which said: "Lovely people, but insane ex-husband". Augusta-Margaret River Shire president Pamela Townsend said the incident had impacted everyone in the area.
Following Friday's massacre, the premier of Western Australia, Mark McGowan, called the shooting "tragic and shocking".