By Holly Hales in Sydney

The courage of those who faced a knife-wielding killer in a Sydney shopping centre has been praised by leaders as details emerge about the culprit and his victims.

Joel Cauchi, 40, fatally stabbed six people and injured at least 12 more in a violent rampage at Westfield Bondi Junction on Saturday afternoon.

NSW Premier Chris Minns said many people ran “towards danger” including Inspector Amy Scott, who shot Cauchi dead at the scene.

“To the ordinary members of the public that cornered and confronted a murderer in the Westfield shopping centre, showing what I would call instinctive bravery under terrible circumstances,” he said on Sunday.

“And of course, Inspector Amy Scott, who ran towards danger and showed professionalism and bravery and without a shadow of a doubt, saved many, many lives in the last 24 hours.

“We’re very, very grateful for the men and women that stood up in Bondi Junction.”

NSW Police Commissioner Karen Webb echoed Mr Minns’ sentiment and commended the state’s first responders for their efforts.

“My thoughts go out to those people that were in the shopping centre, and as the premier has said, showed a great deal of courage yesterday.” she said.

“But also to the emergency services and of course, the police officers who responded to this very traumatic thing.”

NSW Police Assistant Commissioner Anthony Cooke said the man was known to authorities in his home state of Queensland.

“We have received no evidence… no intelligence that we have gathered that would suggest that this was driven by any particular motivation, ideology or otherwise,” he told reporters.

“We know that the offender in the matter suffered from mental health.”

Queensland Police acting assistant commissioner Roger Lowe said Cauchi was living as an itinerant, relocating often across the state.

Cauchi had no known employment or partner and moved to NSW last month.

“We believe he has been sleeping in a vehicle or backpackers according to the family’s information,” Mr Lowe said.

“Understanding that the family do not have regular contact with their son is periodic contact where he may respond to a text message.”

Mr Lowe said Cauchi had not been arrested or criminally convicted over the last four to five years but was known to police.

Six people, five women and one man, were killed in the attack and several others were injured.

Four women aged between 20 and 55 and a man, in his 30s, died at the scene.

A fifth female victim, 38-year-old osteopath Ashlee Good, died at St Vincent’s hospital on Saturday night.

Dr Good’s nine-month-old daughter was stabbed in the attack and is in a critical but stable condition at Sydney Children’s Hospital.

Also among those killed was Dawn Singleton, the 25-year-old daughter of multi-millionaire businessman John Singleton.

The male victim, Faraz Tahir, was a security guard at the shopping centre and had arrived in Australia after fleeing persecution in his home country of Pakistan, Ahmadiyya Muslim Community Australia has confirmed.

Two of the six victims were from overseas and have no family in Australia, Mr Cooke said.

Members of the public paid their respects to victims of the Bondi Junction stabbing attack. (Dean Lewins/AAP PHOTOS)

At least 12 others, including nine women, two men and Dr Good’s daughter, were hospitalised after suffering stab wounds in the attack.

Prime Minister Anthony Albanese said Ms Scott, who was lunged at by Cauchi before he was shot, no doubt saved lives.

“The wonderful inspector who ran into danger by herself and removed the threat… without thinking about the risks to herself,” he told reporters.

“We also see the footage of ordinary Australians putting themselves in harm’s way in order to help their fellow citizens.”

Mr Albanese along with Mr Minns and local MP Allegra Spender laid flowers at the scene on Sunday afternoon.

Prime Minister Anthony Albanese and AFP Commissioner Reece Kershaw respond to the stabbing tragedy. (Lukas Coch)

Federal Opposition leader Peter Dutton said there was heroism amongst the horror.

“We thank everyday Australians who helped each other get to safety and those who provided comfort to others in distress,” he said on social media.

Ms Webb said Insp Scott was doing well under the circumstances.

“She showed enormous courage and bravery. It was an awful situation … but it could have been much worse,” she said.

The shopping centre is closed and will be an active crime scene for days.

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