The bodies up to five people, including children, have been found in a Western Australia home by police on Sunday.
Investigators went to the house in suburban Perth after a man, aged in his 20s, presented himself to a regional police station.
Officers “discovered the deceased bodies of several people including children”, police said in a statement.
“The man is currently in custody and assisting police with their inquiries. There are no ongoing concerns for public safety as a result of this incident,” police added.
It was unclear how the victims died or any details about their connection with the man in custody.
Assistant Police Commissioner Paul Steel told reporters the investigation was still in a “very early stage”.
A distraught neighbour said she often saw children playing in the front yard of the house at the center of police investigations.
“How could someone do that to their own children? It’s sickening to think someone could do that.”
Another neighbour told WA Today she didn’t know the home’s occupants personally, but would often wave and say hello as she walked past.
“It’s taken us by complete shock,” she said. “It’s just horrific on every level.”
Neighbour Vagner de Souza told the ABC he regularly saw a family in the house’s yard.
“Just a normal family, you would never imagine anything like that happening,” he said
The deaths came three months after a father shot dead his teenage son and daughter at their home in Sydney before turning the gun on himself.
It also follows the deaths of seven people, also in Western Australia, when a grandfather shot dead his wife, daughter and her four children in a mas