Mum and children identified as father speaks to police
"She was a really nice lady," a neighbour said.
"It is really sad.
"The kids were always dressed nice.
"She was polite. She was really friendly.
"No one around here would say a bad thing about her."
He described the woman as a doting mother of three who was always taking her children for bike rides and ice cream.
A Victoria Police spokesperson said the exact circumstances were unclear at this point.
"A man is assisting police with their enquiries,'' the spokesperson said.
"A crime scene has been established and detectives from the Homicide Squad are attending. The exact circumstances around the incident are under investigation and we will provide more information when it's appropriate to do so. There is currently no ongoing threat to the community.''
The man was taken away in an ambulance under police guard.
Helicopter vision shows children's toys in the backyard.
Neighbour Marie Groves described the people living in the house as a "beautiful family".
"She was gorgeous. She was lovely. They were a beautiful family," Ms Groves said.
"She really loved her job, loved her babies, loved her family. She's so protective of them.
"I can't believe it - those babies."
Ms Groves said the woman was a physiotherapist and her husband was a mechanic.
She revealed the couple had plans to rebuild their house.
Ms Groves said last time she had seen the woman was before Christmas, and said she seemed "a bit quiet" but nothing seemed wrong.
A neighbour spoken to by the Herald Sun, who lives next door to the crime scene, said he was shocked to learn four people were found dead.
"It's my next door neighbour,'' he said.
"I heard the police and I went to check on what was happening and they (police) told me to go home and stay inside.
"I don't know what happened. There's three young kids there.
"They have been very nice.
"I saw the man (my neighbour) sitting in a chair. I'm in real shock.''
Another neighbour, Johnie, said he was frightened to see a heavy police presence saturate his street.
"It's a bit too much for a local neighbourhood like this," he said.
"The police Chopper was over our house for an hour."
Victoria Police will hold a press conference at 4:30pm.
- More to come
Originally published as Four people found dead at Tullamarine property
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