The bodies of Katrina Miles, her children and her parents, Cynda and Peter Miles, were found early on Friday in what police are treating as a murder-suicide, confirming they are not looking for any suspects.

Police are now focusing on grandfather Peter Miles as the gunman and have launched a massive investigation to establish what went on in the neat Osmington Road property, located just a 15-minute drive from the trendy wine and surfing mecca of Margaret River.

The seven members of the family’s three generations all lived on the property, known as Forever Dreaming Farm, which was owned by Cynda and Peter.

Police said the bodies of two adults were found outside near a shed that had been converted to living quarters, while the other adult and children – Ryan, Taye, Ayre and Kadyn, aged eight to 13 – were discovered inside when police were called to the property.

Neighbours told investigators of hearing gunfire in the pre-dawn darkness but thought it was nothing more than kangaroo hunters.

Katrina Miles was devoted to her children – all of them autistic and reportedly home-schooled – as indicated in this post from a fortnight ago about her experience at a local swim school.

“3 years ago my 4 autistic children were able to do funded swimming lessons with Lynda,” she wrote.

“Prior to this swimming lessons were very, very tricky; navigating the pool area, all the assault on the senses (noises etc), focusing on the lesson and being able to coordinate their bodies for strokes all needed specialised care. Lynda is very kind, vibrant and really thinks about my kids needs…

“My kids love Lynda and her sense of fun, she helps them be confident with their swimming skills but also with their sense of belonging in our community.”

As the close-knit community of mostly small-acreage farms reels at news of the mass murder-suicide, a local resident who did not want to be named described the family as “hugely respected” and “a great asset to the community”.

“It’s just absolutely really shocking,” he told AAP.

“I can’t imagine just how disturbed someone is, how they could do that.”

Former local councillor Felicity Haynes who lives on a neighbouring property told the ABC the family were “caring neighbours”.

“They were just such lovely people,” she told the broadcaster.

“They were a very socially-aware family, doing their best to create a safe community, and that is why it is so shocking to think that could be destroyed so quickly.”

 Ms Haynes later told radio station 2GB the tight-knit community knew each other well and was devastated by the shooting.

“All the neighbours are in shock… everyone along Osmington Road. I mean, this is a very quiet peaceful community, mostly rural blocks. We all know each other, all support each other – in fact, the whole Osmington community was very much united against this coal mine that was going to be erected right opposite the place where this tragedy occurred,” she said.

Augusta-Margaret River Shire president Pamela Townshend said Osmington Road was home to a particularly tight sub-community.

“There’s a lot of giving each other vegetables, cooking each other meals, looking after each other when they’re ill, they’re very connected in deep ways,” she told AAP.

“Such a horrific killing is going to affect our community very deeply. We’re all connected to each other one way or another.”

Premier Mark McGowan described the incident as a “shocking tragedy”.

“Clearly this is a distressing day for Western Australia,” he said, adding that it was “a dark day for every family member or friend of the people involved.”

On the farm’s website, Cynda Miles said the farm, which they reportedly bought in 2014, was their “forever farm”.

“Forever Dreaming is our forever farm. It is here that we will grow as much of our food as we can, sit on the veranda and watch the birds, and watch the grandchildren immerse themselves in the animals and everything else that happens on a daily basis,” she wrote.

Peter Miles worked as a farmer and teacher and was formerly the manager of the Margaret River High School farm while his wife, Cynda, had been at the forefront of the sustainability community, leading recycling initiatives including Cynda’s Soft Salvage.

• Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14.
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