Sydney stabbing suspect's family reported him missing before knife rampage

The family of a man accused of killing a woman in a stabbing rampage in Sydney’s CBD reported him missing before the alleged attack, police say.

Mert Ney, 21, allegedly stabbed a 24-year-old woman to death in an apartment before embarking on a stabbing rampage in Clarence Street on Tuesday afternoon and injuring a 41-year-old woman.

NSW Police Commissioner Mick Fuller said Ney, from Marayang near Blacktown, was expected to be charged with murder as well as serious assault after he allegedly unleashed "terrifying carnage" in the city.

Mert Ney being detained by police in Sydney following the alleged rampage. Source: AAP

The commissioner has now revealed Ney had been listed by his family as a missing person before the attack.

It is believed they had concerns for his welfare following a domestic violence incident.

"That is not unusual in terms of what we see day-in-day-out in some houses across NSW (but) that is not a common theme for someone to then take the next step of coming onto the streets of Sydney with a knife and killing people and threatening to kill people," Comm Fuller told reporters on Wednesday.

Ney has undergone surgery at Royal Prince Alfred Hospital for a cut to his knee.

But police hope he will leave hospital on Wednesday afternoon.

A women is taken by ambulance from Hotel CBD at the corner of King and York Street in Sydney. Source: AAP

‘He could have killed more people’

Police also revealed the 21-year-old would have likely killed more people if it wasn’t for heroic bystanders who stopped him.

“We’re rebuilding his movements, predominantly through the CCTV footage from City of Sydney council,” Comm Fuller told media on Wednesday.

“We actually have footage of him in the city. We know that there was phone contact between him and the 24-year-old victim.”

The 41-year-old woman who was injured in the attack is recovering in hospital and police say she is “very, very lucky to be alive”.

“You would say with some confidence that he went on to the street to kill more people. And the fact that she’s alive is a miracle and the fact that other people are alive is mainly because of the behaviour of so many citizens,” Comm Fuller said.

In footage already reviewed by police, the commissioner said they had “seen what probably could have happened”.

“Which would have been a lot more people injured and/or killed if it wasn’t for the courage of a number of people who stood up yesterday in a very high-risk situation,” he said.

The man started his alleged rampage in a balaclava before he was taken by citizens. Source: 9News

Material about mass shootings found on USB

Comm Fuller said the rampage had not been classed as a terrorist incident and the "lone actor" had no known links to terrorist organisations.

Ney was, however, carrying a USB stick with information about recent mass casualties in New Zealand and the United States.

While he had a history of mental health issues and an "unremarkable" criminal history, his motive remains unclear.

"Having some footage saved on a USB drive is not a leap far enough for me to say that this is a terrorist incident – but obviously it's extremely concerning and it is the starting point of a long-term investigation," Comm Fuller told reporters.

A man with a chair confronted the alleged stabber. Source: Twitter/ @Ayusha77

"What he has on social media, what we may well find in his bedroom, will hopefully give us, and shine more light on, why this crime happened."

Detectives were on Wednesday searching Ney's family home in Marayong and a property in Blacktown, where it was believed he was staying.

"If we can link him to terrorist activity, then the offences that follow would see him locked behind bars for a very, very long time," Comm Fuller said.

Suspect described as loner at school

Former pupils at Blacktown Boys High School which Ney attended described him as “a bit weird”.

“He just had a vibe, he was just an odd person – he didn't have many friends,” one anonymous school friend told the Daily Mail.

Another said he had posted to converting to Islam on Facebook but never thought he’d “go this far”.

With AAP

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