A passer-by who protected a woman during a stabbing rampage on a major Sydney highway was "unbelievable", another witness says.
Six people were hurt after a driver crashed at Engadine, in the city's south, began stabbing his passenger and attacked those trying to stop the assault on Sunday morning.
The driver, who is yet to be charged, reacted violently when his passenger changed the car radio station, witnesses were told.
Steve Mace, the chair of NRL club Cronulla who witnessed the incident, lauded a fellow passer-by who intervened and put himself between the woman and the knife-wielding driver despite suffering a serious stab wound.
"Getting her in and out of that car to dodge the stab wounds was unbelievable," Mr Mace told Sydney radio 2GB on Monday.
The men initially pulled the bloodied woman from the car, only to return her to the car when the driver ran around to continue the assault.
Video from witnesses shows a man holding the passenger door shut as the driver, with blood across his white shirt, moving about the rear of the car and shouting.
"The first time you were dodging swings, like deadset swings, and all he was carrying on was about a radio station getting changed," Mr Mace said.
"Then it was 'You're all gone anyway because you've all got the jab'.'"
The woman also needed to be calmed after she saw her partner run up the street when police arrived.
"She's clearly brainwashed in the environment she was in - all she was worried about was him and what the police were doing to him," Mr Mace said.
The woman and her helper remain in hospital, but both improved overnight to a stable condition.
The driver was in a serious but stable condition in hospital on Monday morning.
He was known to police but not for domestic-violence matters involving the woman, investigators said.
A police officer was also seriously injured while arresting the driver, while two people were injured when their car was hit by the attacker's car.
New South Wales Premier Chris Minns credited the "incredibly brave" people who intervened during the attack.
He noted a "cruel irony" in the domestic violence-related incident occurring as NSW Police ran a major operation targeting the crimes at the weekend, arresting 550 people.
"Unfortunately, (domestic violence) is increasing in NSW and we need to throw more resources at it," he said.
Prime Minister Anthony Albanese described the episode as shocking and distressing.
"We're thinking of all those who were injured and hoping for their quick recovery," he posted to social media platform X.
Investigations into the incident are ongoing and charges are expected.
