Police have formed the preliminary view that the Melbourne mother found dead alongside her three children was responsible for all four deaths.
Her husband was released without charge on Thursday night.
“Investigators do not believe the 48-year-old man was involved in the incident and police are not looking for anyone further in relation to the matter,” Victoria police said in a statement on Friday.
“Homicide Squad investigators have formed the preliminary view that the 42-year-old woman is responsible for all four deaths and on completion of their investigation, a report will be provided for consideration of the coroner.”
The body of the 42-year-old woman, identified by several media outlets as Katie Perinovic, was found dead inside her Tullamarine home in the city’s northwest about 12.20pm on Thursday.
Her three children were also discovered dead inside the Burgess Street address by paramedics. They have been identified as Claire, 7, Anna, 5, and Matthew, 3.
Ms Perinovic’s husband and the children's father, Tomislav Perinovic, 48, called emergency services to report the deaths and was discovered in the front yard of the home unharmed.
An extensive forensic examination of the scene has been conducted.
Detectives have also spoken to a large number of people, including the family, friends, and neighbours of the deceased.
“I know there will be many people in the community struggling to understand and come to terms with this tragedy,” Acting Deputy Commissioner Robert Hill said on Friday.
Neighbours’ shock over ‘beautiful’ family
Neighbours have revealed their shock over the deaths, many saying the “beautiful” family was an integral part of the community.
Nearby resident John Constantino revealed he spoke to Ms Perinovic less than 24 hours before her death and hadn’t noticed anything out of the ordinary.
"I was watering the garden about 7.30pm and she walked past and she seemed happy and everything," he told The Age.
"She asked me what I was going to do tomorrow, I said, 'I might mow the lawn' and she said 'yeah, it's not going to be a hot day'."
However a friend has recalled a previous meeting several months ago where Ms Perinovic appeared distant and dejected.
Marie Groves said Ms Perenovic was far from the “smiley-faced Katie” the neighbourhood knew at her daughter’s birthday party on November 29.
“On that day she did seem to be a bit withdrawn – that was not usual – she was very quiet … in retrospect maybe that was a pointer,” she told the Herald Sun.
The family’s next-door neighbour told the publication Ms Perinovic had given him and his wife plums the day before.
On Friday, members of the community attended the family’s home to leave flowers and tributes.
Mother left job ‘unexpectedly’
Mr Hill on Thursday refused to detail the injuries suffered by the mum and her children.
"The loss of life is tragic in any circumstances," he said.
"But when it involves children, it makes it even more heart-wrenching."
Acting Assistant Commissioner Mark Galliott said the situation was "difficult to comprehend".
"This will have long-lasting effects on the police that attended, on extended family, the community, the neighbourhood, the emergency services and everybody else involved," he said.
Ms Perinovic was a physiotherapist who had only recently returned to work after taking time off to care for Matthew, Ms Groves said.
According to the Herald Sun Ms Perinovic left the clinic "unexpectedly" three months ago.
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