Four people, including three children, have died after a car was allegedly set alight in the Australian city of Brisbane, police said.

The children, all under the age of 10, were found dead in the car by emergency responders, said Queensland Police.

A man known to the victims has also died, while a woman suffered extensive burns and has been taken to hospital.

“It’s a horrific scene,” Det Insp. Mark Thompson told reporters on Wednesday.

“It is very early in the investigation, but the vehicle was fully involved in fire upon police arriving,” he said. Paramedics said they had also treated a passerby, who had “tried his best to get to the car”. He had suffered some “facial burning” and also been taken to hospital, a Queensland Ambulance spokesman said.

Residents on the street told Australian media they had seen the woman jump out of the car while she was on fire.

She had yelled, “he’s poured petrol on me”, one witness told The Australian newspaper.

Police said it was too early to confirm details about the victims’ identities, and refused to comment on questions about family violence.

Queensland’s Police Minister Mark Ryan told parliament about the “horrific incident” on Wednesday.

“My thoughts are with all of those affected by this terrible tragedy,” he said.

Prime Minister Scott Morrison said his “heart goes out to the families and community going through this tragic time and the emergency responders confronting what would be a shattering scene”.

Federal MP Terri Butler said she was “horrified and devastated” by the incident.