By Duncan Murray in Sydney

Missed opportunities to stop a mass stabbing at a major shopping centre will be probed at an inquest as family of those killed heard the attacker stopped receiving treatment for serious mental illness years earlier.

Joel Cauchi fatally stabbed six people and wounded about a dozen others in the violent attack during Saturday trade at the busy Westfield Bondi Junction in Sydney’s eastern suburbs in April.

An inquest will examine the circumstances of the attack with the aim of preventing a similar tragedy.

Counsel assisting Peggy Dwyer SC told an initial directions hearing on Tuesday that Cauchi stopped receiving treatment for schizophrenia from around early 2020, leaving him homeless and drifting between his home state of Queensland and NSW.

“The evidence suggests a deterioration in his mental health over that time,” she said.

The inquest, due to be held in April and May 2025, will look at issues including whether early intervention could have prevented the attack, which ended when Cauchi was shot dead by a police officer.

It will also probe the response of security guards and emergency services to the attack and consider making recommendations for improvements.

Ashlee Good, 38, Dawn Singleton, 25, Jade Young, 47, Pikria Darchia, 55, Yixuan Cheng, 27 and 30-year-old security guard Faraz Tahir were all killed in the attack.

At least 10 others were taken to hospital with stab wounds, including a nine-month-old baby who was released following treatment.

Ms Singleton was the first to be killed as she waited in line at a bakery after Cauchi produced a large Ka-bar knife, the type used by the US Marines, and stabbed her just after 3.30pm.

From there, he either stabbed or attempted to stab any person he came close to, Dr Dwyer said.

“In less than three minutes, 16 people were stabbed and injured in what appeared to be indiscriminate attacks,” she said.

How the victims, who were predominantly women, were chosen would be one of the aspects explored, Dr Dwyer added.

Ms Good was struck once before turning to see Cauchi in the process of attacking her baby in a stroller.

“She ran at him and fought him off, receiving another stab wound as a result of that,” Dr Dwyer said.

NSW Police inspector Amy Scott ended Cauchi’s rampage when she fired three shots at him on level five of the complex as shoppers fled, hitting him twice, in the neck and shoulder.

Just five minutes and 43 seconds passed between the start of the attack to the 40-year-old being shot dead.

Mr Tahir’s siblings Sheraz and Muzafar Ahmad said they planned to watch CCTV footage of the attack to better understand what happened to their brother.

“He was on duty at that time and he just tried to stop the attacker – and he ended his life,” younger brother Sheraz Ahmad Tahir said outside the court.

NSW State Coroner Teresa O’Sullivan expressed her condolences to all of the loved ones of those who were killed.

“The events of the 13th of April remain raw and painful for all those that have been impacted,” she said.

There was significant public interest in how large companies like Scentre Group, which operated the shopping centre, prepared for mass casualty events, Dr Dwyer said.

The evidence was expected to show no alarm sounded within the Westfield centre until about one minute after Cauchi was shot dead and more than seven minutes after the first victim was attacked.

Such mass casualty events were rare in Australia and could expose deficiencies or flaws in the systems intended to deal with them, Dr Dwyer said.

“When they do happen, they happen quickly and they cause chaos,” she said.

“They provide an opportunity to learn with a view to saving lives … in the future”

The inquest is due to run from April 28 to May 30.