Police search family home of 20-year-old, who has spent night in hospital after knife attack

This article is more than 1 year old

This article is more than 1 year old

A man who allegedly killed a woman in Sydney’s central business district before attacking others on a busy city street is expected to be charged with murder on Wednesday.

Officers have been searching Mert Ney’s family home in Marayong in Sydney’s west after Tuesday’s violent rampage, as well as another address at Blacktown.

The 20-year-old, who has spent the night under police guard in hospital, had a history of mental health issues. Overnight he underwent surgery for a cut to his knee.

Sydney stabbing: one woman killed and one injured in 'terrifying carnage' in CBD Read more

“It is unclear when he will be deemed medically fit to speak with investigators,” New South Wales police said on Wednesday.

On Wednesday office workers who were confronted by Ney during his six-minute rampage through the city returned to the scene, many appearing emotional.

“Looking back on it now this was a guy who had just killed somebody,” witness Vee Morgana told reporters.

“I saw the guy stab someone and I didn’t know how many people he’d stabbed [before that].

“There was a moment just here on Clarence [Street] it was just me and him just 10 metres apart. I only had my phone on me and there was a moment where I just froze and luckily a [fire fighter] with a crow bar and a guy with a chair came either side of me and they spooked him a little bit.”

On Wednesday police revealed the woman allegedly killed by Ney was Michaela Dunn, a 24-year-old from Sydney’s west.

Dunn had been working as a sex worker from her Clarence Street apartment, and police said their initial inquiries indicated Ney had attended the unit for an appointment at about 1.30pm. He was captured on CCTV leaving the building at about 1.50pm.

The footage, obtained by Channel 7, shows Ney taking a photo of himself as he left the Clarence Street building.

Earlier on Wednesday the police commissioner, Mick Fuller, said Ney was expected to be charged with murder as well as serious assault. Police have formed Strike Force Lalchere in response to the stabbings.

“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,” Fuller said.

Play Video 1:25 Sydney stabbing: moment man was restrained by public after rampage – video report

Ney’s family had reported him missing and 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,” Fuller said.

The 20-year-old jumped on cars and yelled at bystanders to “shoot me in the fucking head” before being restrained by members of the public – later lauded as “heroes” by police – who used cafe chairs and a milk crate to pin him down.

About an hour after the man’s arrest, the body of a 24-year-old woman with a laceration on her neck was found inside an apartment in Clarence Street, in central Sydney. Fuller said Ney had been at the apartment for “business purposes”.

A 41-year-old woman was stabbed in the Hotel CBD, on the corner of Clarence and York streets. She was taken to St Vincent’s hospital suffering a non-life threatening injury from a single stab wound to her back.

Police say Ney did not have any known links to terrorist groups, and that he had acted alone. The attacks are not being treated as a terrorist attack, Fuller said.

The 20-year-old did, however, have “some ideologies in relation to terrorism” and the joint counter-terrorism team would examine if the terrorism threat needs to be reassessed.

“There was certainly information found on him about other crimes of mass casualties and mass deaths around the world,” Fuller said, adding that the material had been discovered on a USB drive.

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Video footage shows Ney, who was armed with a large butcher’s knife, yelling “Allahu Akbar” while wandering the CBD. He also yelled at bystanders, “Shoot me, fucking shoot me in the fucking head, shoot me, I want to fucking die.”

The Daily Telegraph reports that he faced a magistrates court in June after being found with knuckledusters. He pleaded guilty to possessing a prohibited weapon and was sentenced to a conditional release order for nine months.

Superintendent Gavin Wood said the bystanders who had apprehended the man were “significantly brave people”. “To approach a person with a mindset of obviously what this person [had], with clear evidence of a stabbing previously, these people are heroes.”

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He said their actions had prevented others from being hurt. “These members of the public, going about their day-to-day business, have jumped into a situation which was extremely dangerous and hostile and they have brought a person, who we will be alleging has stabbed an innocent person for no specific reason, into custody and allowed us to do our job.”

Scott Morrison characterised the attack as deeply concerning and said his thoughts were with those affected by the incident.

“The attacker is now in police custody following the brave actions of those who were present at the scene and were able to restrain him,” the prime minister said on Twitter.

Police minister David Elliott said he will make sure police consider any exposure Ney had to government services in the recent months as part of their investigation.

“We want to make sure that we learn any lessons that need to be learnt from this particular occasion,” he told reporters.

Police are appealing for witnesses to come forward. In particular they are seeking security surveillance, dashcam and mobile phone footage.