Neighbours described Katie Perinovic, 42, as a beautiful woman and protective mother after she was discovered alongside her children Claire, seven, Anna, five, and Matthew, three, inside their home in Tullamarine on Thursday.

Detectives from Victoria Police’s homicide squad arrived about 12.20pm to find father Tomislav Perinovic, 48, with paramedics in the front yard of the three-bedroom brick house.

Acting deputy commissioner Robert Hill described the incident as tragic, saying the homicide squad would continue examining the scene throughout the evening. “The loss of life is tragic in any circumstances but when it involves children, it makes it more heart-wrenching,” he said.

Commissioner Hill said Mr Perinovic was a person of interest but it would be “grossly unfair” for any assumptions to be drawn this early in the investigation.

“As to who is culpable for the death of the four people, that is yet to be determined and we should not draw any conclusions,” he said. “We should not assume culpability on the basis that we have a male assisting us with inquiries.

“We just need to understand the facts … unfortunately they’re not known to us but will be in the fullness of time.”

He said there was no known history of family violence linked to the family and detectives had not ruled out the possibility of a murder suicide.

Commissioner Hill said Mr Perinovic had called emergency services to the scene.

Aerial photos of the property show toys scattered across a grassy backyard while a gum tree grows from the nature strip at the front of the brick home.

Neighbour Marie Groves, 49, said Ms Perinovic would often bring her three children over for playdates, describing her as a “beautiful, protective” woman. “She was a well known, beautiful and a very tall lady, very gorgeous … every time she walked past she always had a smile on her face (and was) always chatting to everybody,” she said. “They did come for playdates and (the mother) was always very upbeat.

“This is a neighbourhood where the kids know each other, the families know each other and … if you’re not around, we keep an eye on each others’ places.”

Ms Groves felt compelled to tell her youngest daughter of the tragedy as she used to play with the Perinovic children.

“I just told my youngest who was close playmates (with them) … I had to otherwise she would have heard it on the street.”

Ms Groves, who lives around the corner from the Perinovic house, said Tullamarine might be big, but “this particular part” was small and like a family.

“Everyone knows everyone, all the kids know each other, and go to the same schools and parties,” she said. The Perinovic children attended dance classes and a playgroup locally, and they would “be across here all the time with their bikes”.

Her husband, Steve Groves, 49, said the four deaths were “devastating”. He said the children came to his house to celebrate his daughter’s birthday in November.

“(In December) I saw her once in the park … with her three kids and we just had a chat and everything seemed normal,” he said.

Another neighbour further down the street, Sapi Safou, 35, said she did not know the family, but the neighbourhood was “quiet”. “To have this going on, it’s a shock to our neighbourhood,” she said. “To find out what happened, it’s so sad.”

The tragedy comes just days after another mother and her three young girls were found dead inside a burnt-out home in Glen Waverley, in the southeast, after a blaze tore through the property early on Sunday morning.

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