A Melbourne mother found dead alongside her three children is believed to have killed them before taking her own life in what Australian police are treating as a murder-suicide.
The bodies of Katie Perinovic, her daughters, Claire, 7, and Anna, 5, and son, Matthew, 3, were discovered inside their Tullamarine home on Thursday afternoon, sending shockwaves through the normally "quiet" community.
Katie Perinovic's husband, Tomislav, 48, made the call to emergency services and was questioned by police before he was released without charge.
"Investigators do not believe the 48-year-old man was involved and police are not looking for anyone further," police said today.
"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."
Acting Deputy Commissioner Robert Hill said police would work to support the families of those involved and ensure they get the help they need.
"I know there will be many people in the community struggling to understand and come to terms with this tragedy," he said.
"This has also been an incredibly difficult time for the police and paramedics, who responded and attended the scene yesterday.
"This has been an incredibly heart-wrenching experience for all concerned."
Neighbours Daniel and Vicky Schembri have been residents in Burgess St, where the Perinovic family lived, for 48 years.
They revealed that the last time they saw Katie Perinovic was on Wednesday — less than 24 hours before she and her three children would be found dead.
She was dropping a bag of plums off at their door.
"She knocked on the day around 5.30 in the afternoon, I said 'Thank you very much', and she said 'Bye'," Daniel Schembri said.
The Schrembis said Tomislav Perinovic moved next door about 25 years ago before he met his future wife.
"Then he got a girlfriend, and he said, 'I'm getting married soon'," Schrembi said.
"She — Katie Perinovic — was happy. She came round one day and said, 'I'm pregnant'. As soon as they got married she fell pregnant.
"So we started buying things for the kids, for Christmas and Easter."
The Schembris saw the "very active" kids all the time, when they would play and ride their bikes in the street.
The oldest, Claire, was getting dancing lessons. The youngest was about to start school.
"Now, in heaven," Daniel Schembri said. "They were very good kids."
The Schembris were home on Friday. But, like other neighbours, the first indication they had that something was wrong was seeing emergency services rushing to the street.
"We saw Tom sitting on the chair with his hands behind his back," he said.
"He was quiet — numb. And then they took him in the police car. He was really stressed, believe me.
"But a police officer was there and he said, 'Get inside, and stay there' — so I was too scared to go out."
Daniel Schembri said it "breaks my heart" to think of the three kids wishing them a Happy New Year, eating lollies, just two weeks ago.
"How could this happen?" he said.
On Friday mourners laid flowers and cards at the property.
One child, Anabelle, left her handwritten note at the gates just moments before detectives left the scene with large bags of evidence.
"To Claire, Anna, Matt and Katie. You always are very nice, loving, caring and Claire was my bff [best friend forever] always. Love from Anabelle," the note read.
Lee, a team manager at the West Meadows paramedics unit, also laid flowers at the scene and took a moment to reflect outside the house.
Speaking to NCA NewsWire, he said about five of his paramedics responded to Thursday's horror and were "shaken".
"The loss of three kids deeply affects everyone, including our staff," he said.
"It's not a normal thing. Yes, we have distressing elements to our role, but incidents like this are rare.
"They're [the paramedics] affected - it's tragic, and as West Meadows paramedics we wanted to share our condolences with the family and the rest of the community."
Family friend and neighbour Marie Groves said the last time she had a proper conversation with Katie was on November 29 for her daughter's birthday.
She said Katie was "unusually withdrawn and quiet" that day.
"It's incomprehensible this has happened," Groves said on Friday morning
"She was such a feature of the neighbourhood, she was smiley-faced Katie.
"On November 29, I got her to come across and help celebrate my daughter's birthday with my kids.
"She was only there for a short period … her two older girls were very similar to my younger daughters, they were chatting and laughing – typical 7-year-olds. They were beautiful kids.
"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."
Groves said she didn't know Katie's husband, Tomislav, very well.
"This would never have been on the radar of something that could've happened to her family because she was so protective of them," she said.
A small group of suited detectives arrived at the home about 9.15am today and went inside the house, which was still cordoned off with police tape.
One, wearing masks and gloves, took video footage of the front of the house.
Two uniformed officers remained positioned out the front in a police vehicle.
One neighbour, who wanted to remain anonymous, told NCA NewsWire he knew Katie's three children from school.
"It's devastating what happened. The kids went to the same school as my kids. It's really sad," he said.
Another neighbour, Irene, said she was watching the tragic events unfold on her television just a few doors down when a police officer knocked on her door for any information.
She said the family had moved into the street a few years ago.
"Sometimes I've seen them to go with the little kids on the bicycle," she told NCA NewsWire.
"But it's normally a very quiet street; that's why I was very shocked. It's awful."
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