A knife-wielding man who killed six people in a Sydney shopping centre before being shot dead has been identified by Australian police.

Joel Cauchi, 40, sent the crowded Westfield Bondi Junction complex into panic on Saturday when he began stabbing people with a long blade.

Five women and a man died. Several others, including a baby, were injured.

Authorities said the attack was most likely “related to the mental health of the individual involved”.

In an update on Sunday, New South Wales Police Assistant Commissioner Anthony Cooke said they were still trying to notify families of the victims.

“Two of them appear to have no family in Australia,” he told reporters.

He said Mr Cauchi, who was from Queensland, was previously known to police and had bought a storage unit in Sydney.

The assistant commissioner reiterated that the attacker did not appear to be motivated by “any particular ideology or motivation”.

The nine-month-old girl “had surgery overnight and is currently in a critical condition and is in ICU,” Health Minister Ryan Park told ABC news.

“Now, we certainly are hoping that she gets through this but there is a long way to go.”

Her mother, Ashlee Good, was among those killed. Witnesses have told local media that Ms Good managed to pass her baby to bystanders in the moments after she was wounded.

“The mum got stabbed and the mum came over with the baby and threw it at me and (I) was holding the baby,” one man told Nine News.

Ms Good’s family said they were “reeling from the terrible loss of Ashlee, a beautiful mother, daughter, sister, partner, friend, all-round outstanding human and so much more”.

“We appreciate the well-wishes and thoughts of members of the Australian public who have expressed an outpouring of love for Ashlee and our baby girl,” the family said in a statement.

Ms Good was a “beautiful person”, the owners of a health clinic where she once worked told the BBC.

On Sunday, tributes of flowers began to pile up outside the huge shopping centre in Sydney’s affluent east.

Prime Minister Anthony Albanese said Australians were “waking up to try to deal with the shock and trauma” of what had happened.

Describing the attack as “unspeakable and really just beyond comprehension”, Mr Albanese again praised the actions of a lone senior policewoman who confronted Mr Cauchi and shot him dead as horror gripped the mall.

“The wonderful inspector who ran into danger by herself and removed the threat that was there to others, without thinking about the risks to herself,” the prime minister said, thanking her and emergency teams.

State officials said nine people had been taken to hospital after the incident, and another three people had sought medical attention overnight. About 40 paramedics were initially involved in the response.

The shopping centre remained closed on Sunday and forensic investigators pored over the scene.

Many world leaders have expressed shock. New Zealand leader Christopher Luxon said all New Zealanders were thinking of those affected, while UK Prime Minister Rishi Sunak said they were “in the thoughts and prayers of the British people”.

Pope Francis said he was deeply saddened by the “senseless tragedy” and offered prayers. King Charles added he and Queen Camilla were “utterly shocked” and “our hearts go out to the families and loved ones”.