Australia is mourning the deaths of a woman and her three children who were “senselessly murdered” in a car fire, Prime Minister Scott Morrison has said.

Police are yet to confirm reports the father, ex-rugby player Rowan Baxter, set the car alight in Brisbane before stabbing himself to death.

However, they confirmed a history of family violence. Hannah Clarke, 31, and her children were killed on Wednesday.

The case has sparked national outcry over domestic violence.

“Australians all over the country are just shocked, saddened and devastated about what has happened in a suburban street,” Mr Morrison told reporters on Thursday.

“Hannah and her three children [were] so senselessly and maddeningly murdered in what has occurred in a terrible act of violence,” he said.

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On Thursday, Queensland Police said the children and their mother had been killed, and there were no suspicious circumstances concerning Mr Baxter’s death.

“There’s a rising sense of anger in this day and age [that] the scourge of family and domestic violence still can lead to the death of five people,” said Det Insp. Mark Thompson.

What do we know?

Police were first called to the scene in the suburb of Camp Hill the city’s east in at 08:30 local time on Wednesday (21:30 GMT on Tuesday).

They found the couple’s three children – Laianah, 6, Aaliyah, 4, and Trey, 3 – dead inside the car, and their mother burning on the ground beside it. Hannah Clarke, 31, died later in hospital from extensive burns.

Witnesses told Australian media she had screamed “he’s poured petrol on me” and “save my children” when helpers rushed to the site.

They said Mr Baxter, 42, had attempted to stop helpers intervening, before grabbing a knife from the car and stabbing himself to death. Emergency responders were unable to revive him when they arrived at the scene.

Reports have previously referred to Mrs Clarke as Mrs Baxter, but police said she was using her maiden name. She had been driving the car at the time of the incident.

What do we know about the victims?

Family services had previously supported Mrs Clarke with domestic violence issues, and a temporary protection order had been granted by authorities, police said.

She had moved to her parents’ home in Camp Hill with the children last year after separating from her husband. The two had been working out custody arrangements.

“She loved them so fiercely and she was doing everything she could to protect them,” her friend Caitlin Langford told the Australian Broadcasting Corporation.

An online fundraiser started by a relative for funeral costs said Mrs Clarke’s parents had “exhausted themselves to try and help Hannah escape this monster”.

“For all those who knew Hannah, or had even just met her once, [you] would know how much of a beautiful soul she was, her children were her life,” said Mrs Baxter’s sister-in-law Stacey Roberts.

Rowan Baxter was a former member of the New Zealand Warriors rugby league team in Auckland. A team spokesman told News.com.au that Mr Baxter was on their squad, but did not play in any matches.

In recent years, Mr Baxter had run a gym with his wife in Capalaba to the east of Brisbane.

The gym’s website describes Hannah as “an enthusiastic, passionate mother of three” and as a state trampolining champion who had won international medals.

What has the reaction been?

Tributes have poured in for the victims. There has been widespread anger and despair, amid ongoing concern about violence against women.

On average, one woman per week is murdered in Australia by a current or former male partner, according to the Bureau of Statistics.

Former Olympic cyclist Tracy Gaudry said: “#HannahBaxter and her three young children died today in the most despicable way. They should have been safe. Mourning for lives lost, thoughts with family, friends and community.”

“Another week, another man annihilates his wife and family. Australia, we need to talk,” said Australian poet Rob Scott.

Police have been criticised after suggesting the incident may have been caused by “a husband being driven too far by issues he’s suffered”.

“We don’t fumble about like this when terrorists kill,” said Labor MP Brian Mitchell in a tweet. “Why does family violence bring out the hand-wringers for killers of women and kids?”

Angela Lynch, head of the Women’s Legal Service Queensland, also told The Guardian newspaper said she found the police’s rhetoric “very concerning”.

“It’s giving legitimacy to what has occurred, it’s victim blaming,” Ms Lynch said. “It’s saying that she might have caused this through her own actions”.

The case is just the latest of several high profile murder cases where women and children have been the victims.

Last July, a Perth man was jailed to life for murdering his wife, three children and their grandmother in their home in 2018.

The reporting of the incident has also come under scrutiny from people on social media.

“Rowan Baxter set fire to his own wife and kids – but you wouldn’t know that from a lot of media headlines,” said columnist Arwa Mahdawi on Twitter.

Police have said they are still investigating the circumstances. An official update is expected on Thursday.

If you or someone you know needs support for issues about domestic abuse, in Australia you can contact Lifeline on 13 11 14 or Beyond Blue on 1300 224 636. In the UK these organisations may be able to help.