A major investigation is underway with reports that up to seven people have been found dead in a home overnight just outside of Margaret River.
Police confirm the incident is being treated as a murder-suicide.
A male person called police and at around 5:15am this morning, they were called to a property in Osmington.
Upon arrival, 4 children and 3 adults were found deceased. The body of 2 adults were located outside the building
2 firearms were found at the scene.
Other members of the families are in the process of being located.
WA Police Commissioner Chris Dawson said at a press conference a short time ago the incident is a tragic event.
It is very early in the investigation, according to Police Chief Commissioner Chris Dawson.
"This devastating tragedy will no doubt have lasting impact on the families concerned, the whole community and in particular the local communities on our South West," he said.
"This will be a very large scale and detailed investigation."
Homicide squad detectives from Perth are assisting local police for the time.
Anyone with an information regarding this incident, or who saw or heard anything suspicious in the Osmington area this morning, is asked to call Crime Stoppers on 1800 333 000 or report the information online at www.crimestopperswa.com.au
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