Homicide detectives are investigating the deaths of a mother and her three young children at their Tullamarine home in Melbourne's north-west, following an incident that occurred on January 14.
Officers were called to the home around midday, where they discovered the bodies of 42-year-old Katie Perinovic, her three-year-old son Matthew and two daughters Claire and Anna, aged seven and five.
Katie's husband and father of all three children, 48-year-old Tomislav Perinovic, reportedly called emergency services to report the deaths.
Acting Deputy Commissioner Bob Hill said the man was "assisting police with their enquiries", but stressed the investigation was ongoing and it was "very important we do not speculate"
"These people died in suspicious circumstances," he said. "We should not draw any conclusions at this time the fact that we have a male assisting us. We have a long way to go before we can actually understand and appreciate what occurred."
Hill added that as far as police were aware, there was no history of family violence in the household.
When asked if Perinovic was a suspect, police declined to describe him as such.
"He is a person of interest and assisting police with their inquiries," Hill said.
The Herald Sun was told Katie may have been suffering from depression, adding she had worked at a local physiotherapy clinic for the last seven years but left “unexpectedly” three months ago.
Police said they had not ruled out the possibility of a murder-suicide as a possible cause of the deaths, according to The Age.