Father of Sydney mall attacker in tears revealing why he thinks his son 'targeted women'

The father of the man who attacked several people in Sydney last weekend has spoken out.

On Saturday (April 13), Joel Cauchi entered Westfield shopping mall at Bondi Junction, Sydney, wielding a knife.

He proceeded to stab 18 innocent people, killing six of them.

Those who were murdered by Couchi have since been named as Dawn Singleton, 25, Jade Young, 47, Pikria Darchia, 55, Yixuan Cheng, believed to be in her 20s, security guard Faraz Tahir, 30, and 38-year-old Ashlee Good.

Cauchi was also killed in the ordeal and was shot dead by a police officer.

Joel Cauchi has been named a Saturday's attacker (7NEWS)

While there was initially no clear motive for Cauchi's attack, police now believe he'd been targeting women.

"It’s obvious to me, it’s obvious to detectives that seems to be an area of interest that the offender focused on women and avoided the men," New South Wales Police Commissioner Karen Webb told ABC News Breakfast.

"We don’t know what was operating in the mind of the offender and that’s why it’s important now that detectives spend so much time interviewing those who know him, were around him, close to him.

"So we can get some insight into what he might have been thinking."

Five of Cauchi's six victims were women.

The 40-year-old's father, Andrew Cauchi, has since weighed in on his son's apparent motive.

The below video contains security camera footage from the mall attack which some viewers may find upsetting:

Speaking to reporters at his home, Andrew hailed Cauchi as 'a very sick boy'.

"To you he's a monster, to me he's a very sick boy," he told reporters while choking up. "Believe me, he was a very sick boy."

Meanwhile, Cauchi's mother, Michele Cauchi, said her 'heart goes out to the people our son has hurt'.

She continued: "If he was in his right mind, he'd be absolutely devastated at what he's done."

When asked why he might have targeted women, Andrew said: "He wanted a girlfriend. He's got no social skills, and he was frustrated out of his brain."

Tearing up on camera, Andrew said of Joel's poor mental health: "I became his servant. I did everything because I loved that boy."

Asked if anyone had 'let Joel down', Andrew responded: "He let himself down."

Andrew Cauchi said his son was 'very sick'. (7NEWS Australia)

Mr and Mrs Cauchi contacted police on Saturday when they saw CCTV footage of their son on the news.

Cauchi is said to have suffered with schizophrenia and had been living with his parents until five years ago.

He then came off his medication and moved to Brisbane, before returning to his parents' home with five combat knives.

Andrew said his son had a 'fascination with knives' and called police regarding his concerns about the weapons.

Police came, but the bereaved father doesn't know what they said to him at the time.

While Cauchi was known by police, he hadn't been charged or prosecuted with anything prior to Saturday's fatal attack.

If you or someone you know is struggling or in crisis, help is available through Mental Health America. Call or text 988 to reach a 24-hour crisis center or you can webchat at 988lifeline.org. You can also reach the Crisis Text Line by texting MHA to 741741.