Young Sydney mother Ashlee Good, who cradled her nine-month-old daughter Harriet, was one of the victims of a random shopping mall stabbing attack which killed six people, her family confirmed in a statement on Sunday.

Five women and a male security guard were killed in the Saturday attack in the Sydney suburb of Bondi, police confirmed on Sunday, adding that 12 people remained in hospital.

Good, 38, was among the dead. Police said her daughter was in a serious, but stable, condition in the hospital.

“We are reeling from the terrible loss of Ashlee, a beautiful mother, daughter, sister, partner, friend an all-round outstanding human and so much more,” the family said in the statement, which was reported by local media.

“We can report that after hours of surgery on Saturday, our baby is currently doing well,” the family said.

Witnesses told local media Good had been seen cradling her daughter and had sought help from passers-by following the attack.

Good, an osteopath who described herself on LinkedIn as an “articulate and driven” professional, had posted last month about “what a privilege it is to become a parent”, alongside a photo of her with her daughter Harriet.

In Bondi, several people lay flowers at the entrance of the shopping mall where the attack took place.

“It’s such a tragic and shocking event,” said John Tognolini, 65, who came from Katoomba, a town around 90km (56 miles) from Sydney, to lay flowers.

Prime Minister Anthony Albanese said on Sunday he had received condolence messages from around the world, and in the Vatican, a top cardinal said Pope Francis was “deeply saddened to learn of the violent attack in Sydney”.

“He sends the assurance of his spiritual closeness to all affected by this senseless tragedy, especially those who are now mourning the loss of a loved one,” the Vatican telegram said.

Assailant identified

Police on Sunday identified the assailant. New South Wales Police said that Joel Cauchi, 40, was responsible for the Saturday afternoon attack at the Westfield Shopping Centre in Bondi Junction.

NSW assistant police commissioner Anthony Cooke told reporters at a media conference on Sunday that Cauchi suffered from yet unspecified mental health issues and police investigators weren't treating the attack as terrorism-related.