The bodies of a mother in her 40s and her two children were discovered inside a burnt out car in Perth's south on Monday, police have confirmed.
Major Crime Division Detective Inspector Quentin Flatman told reporters on Tuesday a 10-year-old girl and an 8-year-old boy were found inside the burnt out vehicle and are believed to be the children of the adult victim found alongside them.
It is "very, very unlikely" a third party was involved in the deaths, he said.
He said the fire was believed to have been started by one of the deceased.
All three victims were located in the rear of the vehicle and at this stage it appears they died as a result of the fire, Detective Inspector Quentin Flatman said.
"Any untimely death is absolutely tragic, but more so when we have children involved and we’ve seen the repercussions of this have been felt through broader Perth and Australia," Det Insp Flatman said.
A witness had told Nine News he heard what appeared to be several gunshots before seeing the vehicle ablaze.
However Detective-Inspector Flatman said there was no indication firearms were used, and police suspected the noise was the car being engulfed by the flames.
'Shocked' father overseas visiting family
The children's father has been informed and is said to be "in shock". He is currently in the US visiting family and will now return to Australia.
Det Insp Flatman said there was no apparent motive at this stage.
The mother spoke with people in her "immediate circle" on Monday morning and the last known sighting of her was about 11am.
The relationship of the children's parents was said to be "normal" and "happy". They lived near the suburb of Coogee where the vehicle was found.
Extended family members are providing information as part of investigations. Police are also providing support to the victim's family including the father.
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