Joel Cauchi: who was the Queensland man who carried out the Bondi Junction mass stabbing?

Queensland man Joel Cauchi has been named as the man who killed five women and one man at the Bondi Junction shopping centre during a horrific mass stabbing on Saturday.

The 40-year-old was shot dead by a police officer, Amy Scott, who responded to the attack at the busy shopping centre while on duty for an unrelated matter.

Cauchi was known to police in New South Wales and Queensland for mental health-related matters. Police do not believe the attack on Saturday was terrorism-related or linked to any ideology.

Related: Joel Cauchi named as Bondi Westfield attacker who stabbed shoppers

According to his social media activity, Cauchi had been interested in surfing at Bondi beach as well as a range of social activities across Sydney, leaving frequent Google reviews for businesses he attended.

He was diagnosed with a mental illness as a teenager and had received treatment but his mental health has declined in recent years, police have said.

Here is what we know so far.

Who was Joel Cauchi?

Cauchi was a 40-year-old man from Queensland who lived an “itinerant” lifestyle, moving throughout the state before travelling to NSW last month.

Queensland police said he was single with no children, and believed he had been living in a vehicle since arriving to Sydney.

The Queensland police acting assistant commissioner, Roger Lowe, said Cauchi had been diagnosed with a mental illness aged 17, for which he had received treatment, but his mental health had declined “in the last number of years”.

His last contact with family was in March. Police said he would “periodically text his mother with an update to where he was”.

Cauchi was a member of a number of Facebook groups related to social activities throughout Sydney. He had posted in one group as early as last week, wanting to meet others for a surf at Bondi beach.

In January he had posted in a backpackers group seeking people to carpool with and explore Sydney. He also appears to have had a keen interest in astronomy, frequently posting in groups about this.

Queensland police said he was unemployed.

The NSW police commissioner, Karen Webb, said there would be an investigation for “many days, and perhaps weeks” into Cauchi.

Police would work to identify “the movement of the offender [on Saturday and in] the hours, the days, the weeks – his life leading up to yesterday”, Webb told reporters on Sunday.

What was the motive for the attack?

At this stage, police have not identified a motive.

Lowe said Queensland police had been liaising with Cauchi’s family throughout Saturday evening and Sunday. The family viewed footage of the attack on television and “believed that may well have been their son” before reaching out to authorities.

Lowe said the family was cooperating with investigations and had released a statement expressing condolences to the families and friends of victims involved in the tragedy.

“Equally, they have sent a message to the NSW police force with respect to support of the police officer who has killed their son and expressing their concerns for her welfare,” Lowe said.

Webb said whether or not Cauchi was targeting women would be an “obvious line of inquiry”.

What were his previous interactions with police?

Webb told reporters Cauchi was known to police in NSW and Queensland.

“He is not known criminally but he has come to notice of law enforcement in this state and Queensland for mental health-related issues,” she said.

Lowe said Cauchi had never been arrested in Queensland or charged with any criminal offence, with no record in the courts for a domestic violence order.

“He has been in contact with the police, primarily in the last four to five years,” Lowe said. “During that contact we are aware here that this individual has suffered from mental health.”

The last interaction Queensland police had with Cauchi was in December 2023, when he was street checked on the Gold Coast.

At a news conference, Lowe was asked if Cauchi had a knife obsession and had ever called the police on his family for taking away his knives. Lowe responded: “We’re aware of an event in 2023 which we’re investigating.”

But Cauchi had never been charged with any offence relating to knives, or found to possess knives in an unlawful manner that would warrant prosecution, he said.

When did Cauchi come to NSW?

It is believed Cauchi moved from Brisbane to NSW in March, one month before the attack.

He rented a “very small” storage unit in Sydney’s inner city which Guardian Australia understands was only about one cubic metre in size.

Webb would not confirm its contents but said anything found would form part of the investigation. Contents found so far had not revealed any motive, she said.

According to social media, Cauchi was raised in Toowoomba. He left a review for a local restaurant 11 months ago.

Lowe said he had moved around Brisbane to Kangaroo Point and Carina, then back to his family’s residence – understood to be in Rockville, near Toowoomba – over the past few years.

In 2019 the Toowoomba Art Society welcomed Cauchi as a new member, according to a newsletter at the time.

How do people describe his character?

The owner of a knife-sharpening business in Queensland, speaking on the condition of anonymity, told Guardian Australia that Cauchi was an “odd” and “strange” guy.

Roughly three years ago, Cauchi had asked the business to sharpen his two “everyday knives”.

“Which I thought was weird,” the owner said. “He wasn’t a chef or a butcher.

“He goes, ‘Oh no, I just do a bit of dabbling in the backyard with the knives and I use them every day.’”

The business owner said Cauchi had not engaged in small talk and was “very to the point”.

“His expressions, he was just very vague, I suppose you could say,” he said. “No real personality about him, just weird. I heard he leaves one-star reviews on a lot of people’s pages all the time, so just that sort of person”.

Some of Cauchi’s reviews included a show at the Sydney Opera House five months ago (“absolutely loved it!”), a restaurant in Elizabeth Bay seven months ago (“absolutely delicious”) and a club in Sydney one year ago (“the atmosphere is pumping”.)

On the day of the stabbing, Cauchi calmly ate a lunch of red curry chicken with rice just hours beforehand.

Rogate Sianipar, 29, served Cauchi his lunch at Saigon Noodle in Oxford Street mall, about 100m from Westfield, just after midday on Saturday.

“He came at 10am but didn’t have any money so came back at 12,” Sianipar said. “He seemed confused when he ordered. Normal but confused. He opened his wallet and paid.”