A man and his two small children are dead after he drove off a wharf in Port Lincoln on South Australia's Eyre Peninsula.
The three victims have been confirmed by police as locals and identified in media reports as Damien Little and his children Hunter, aged about one, and Koda, aged four.
Police said the man's car was deliberately driven off Brennen Wharf and witnesses reported seeing the white station wagon plunge at speed into water 30 metres deep early on Monday morning.
The entrance to the wharf is gated but it was unclear whether or not the gates were open.
The bodies, the car and a rifle were recovered by police divers about six hours later.
Detective Superintendent Paul Yeomans said it was a heartbreaking incident.
"It's a small community. It'll be a situation where somebody will know somebody will know somebody and no doubt this will affect a lot of people living in Port Lincoln," he told reporters.
"You've got some relatives who have lost relatives."
Mayor Bruce Green said he felt "empty" after hearing the news.
"You're just dumbfounded as to why these things can happen," he told AAP.
"You don't have any power in solving what's just happened or changing what's just happened. So you just feel a little empty."
Hundreds of tributes have been left to the children on social media.
"So tragic - dear little souls. Thoughts are with the families," one woman wrote on Facebook.
"How could anyone do this? They were only children who didn't have a choice. You never hurt your family. Heartbreaking," another said.
One local placed a small teddy bear and flowers on the edge of the wharf on Monday afternoon.
Supt Yeomans said the incident was challenging for everyone involved, including the police divers who had recovered the bodies.
"But my heart certainly goes out for the relatives," he said.
* Readers seeking support and information about suicide prevention can contact Lifeline on 13 11 14 or MensLine Australia 1300 78 99 78
