Crazed knifeman restrained with a milk crate after he killed a woman in horrific Sydney stabbing rampage is accused of assaults inside Australia's most secure prison

By STEPHEN GIBBS, SENIOR NEWS REPORTER, AUSTRALIA Published: 10:32, 19 July 2026 | Updated: 10:32, 19 July 2026 A killer serving decades behind bars for murdering a young woman in Sydney's central business district during a crazed stabbing rampage could see his time behind bars extended after continuing to cause havoc in Australia's most secure prison. Mert Ney stabbed to death 24-year-old Michaela 'Mikki' Dunn, who had been earning money as a sex worker, in her Clarence Street apartment before wounding another woman with a kitchen knife on the corner of York and King Streets in August 2019. Ney's frenzy of violence was only ended when members of the public subdued the then 22-year-old with chairs and a milk crate in a citizen's arrest shown in news bulletins around the world. Now 27, Ney is being held in the High Risk Management Correctional Centre - better known as Supermax - at Goulburn in the NSW Southern Tablelands, where he has continued to cause mayhem. Last Wednesday, Ney was listed before Goulburn Local Court on five sets of charges, the oldest of which dates back to 2024 and the most recent to earlier this year. All up, he is accused of seven jailhouse crimes: four separate assaults upon prison officers, possessing an offensive weapon, being armed with intent to commit an indictable offence and destroying or damaging property. He has pleaded not guilty to the last three of those charges, as well as at least one of the alleged assaults, and all matters will be mentioned again at the same court on August 12. Ney was jailed In May 2021 for a maximum 44 years with a non-parole period of 33 years after pleading guilty to murder and wounding with intent to cause grievous bodily harm.  Killer Mert Ney, who is serving decades behind bars for murdering a woman in Sydney's central business district during a crazed stabbing rampage, has been causing havoc in Australia's most secure prison Ney stabbed to death 24-year-old Michaela Dunn in her Clarence Street apartment in August 2019 before wounding another woman with a knife on York Street. He is pictured in custody Justice Peter Johnson described Ney's actions on the day of the stabbings as 'a cruel, brutal and terrifying attack made for no reason' but declined to impose a life sentence due to his mental illness. 'The offender is a dangerous man and continues to be a dangerous man,' Justice Johnson said, in a statement which has proven to be prophetic. In October 2023, the Court of Criminal Appeal reduced Ney's sentence to a maximum 40 years and ordered he serve at least 30. Before Ney was placed in Supermax he was housed at Parklea Correctional Centre in Sydney's north-west, where in March 2021 he assaulted another inmate. In October that year he was sentenced to a further 15 months imprisonment for assaulting a prison officer.  He set his cell alight in June 2022 and three months later was convicted of intentionally or recklessly damaging property by fire. Goulburn Local Court heard the blaze was caused by aluminium foil being jammed into power points and extensive damage was done to cell's walls, floor and roof. Ney told police he started the fire because he was 'sick of lockdowns', while lawyer Melissa Huseyin informed the court her client was on antipsychotic and antidepressant medication. After killing Micaela Dunn, Ney (above) put on a balaclava and ran through city streets wielding a knife, stabbing 41-year-old Linda Bo in the back and narrowly missing another woman Ney's frenzy of violence was only ended when members of the public subdued him with chairs and a milk crate (above) in a citizen's arrest shown in news bulletins around the world Magistrate Geraldine Beattie accepted Ney had been kept in segregation but noted if the fire had spread through the prison 'the danger to everyone at the jail would have been huge'. 'You're not going to make it any easier for yourself by continuing to commit offences,' Ms Beattie said, before sentencing Ney to 12 months' jail to be served concurrently with his existing sentence.  In December 2022, Ney was ambushed by a prisoner who stabbed him six times in the head and face in an exercise yard at Supermax and in February 2023 he got 15 months more jail for throwing boiling water on an inmate. A Corrective Services officer was taken to hospital in July 2024 after Ney alleged slashed him with a jail-made weapon, causing non-life threatening injuries. He was also accused of destroying a light switch, power outlet and five perspex sheets between July and August that year.  In December 2024 it was reported Ney had been terrorising staff in Supermax where he was considered the 'problem child' of the prison-within-a-prison. The previous month Ney jumped on a computer desk while brandishing a razor blade before kicking an audio-visual screen, forcing officers to deploy gas to subdue him. During his Supreme Court sentencing hearing for Ms Dunn's murder Ney said he had booked an appointment with the young woman without intending to have sex with her. When Nye pulled out a knife Ms Dunn (above) began screaming and he stabbed her in the neck 'to make her be quiet', admitting he 'destroyed lives for no reason' Having killed Ms Dunn, Ney (above, under arrest) sent a short video of himself posing with her body to a friend and told them to call police When he pulled out a knife she began screaming and he stabbed her in the neck 'to make her be quiet', admitting he 'destroyed lives for no reason'. Ney described inflicting further wounds on Ms Dunn after warning his evidence would be 'pretty extreme'. 'It just wouldn't stop,' he said. 'It kept going on for a few seconds. 'I knew she was going to die. There were 20 or 30 stab wounds in her neck - she was going to die, there was no doubt about it.' Having killed Ms Dunn, Ney sent a short video of himself posing with her body to a friend and told them to call police.  'I'm f***ing psycho,' he wrote in an accompanying message. 'I was laughing bro. The fear.'  Ney then put on a balaclava and ran through city streets wielding a knife, stabbing 41-year-old Linda Bo in the back and narrowly missing another woman.  Five bystanders who chased, disarmed and restrained Ney until police arrived were later recognised with bravery medals.  In November 2024, Ney jumped on a computer desk (above) while brandishing a razor blade before kicking an audio-visual screen, forcing officers to deploy gas to subdue him Asked by defence barrister Belinda Rigg SC what he thought was going to happen that day, Ney said: 'I went, this is the point of no return, there is no going back, I've got to fully commit.' Confronted directly with how he felt about murdering Ms Dunn, Ney responded, 'f***ing shit'. 'I'm not even sure why I did it,' he admitted.  Ney listed 'sins' he had regularly committed - taking drugs, drinking alcohol, gambling, excessively watching pornography and hiring sex workers.  When Ney was arrested, he was carrying a USB flash drive containing footage of the Christchurch massacre in which white supremacist Brenton Tarrant shot dead 51 worshippers at two New Zealand mosques in March 2019.  Ney told his sentencing hearing he had watched the footage more than 20 times in the months before he went on his stabbing spree. At his sentencing hearing, Ney listed 'sins' he had regularly committed - taking drugs, drinking alcohol, gambling, excessively watching pornography and hiring sex workers 'I was just really obsessed with it,' he said. 'I couldn't keep my eyes off it.' Ney, who had been diagnosed with anxiety, depression and obsessive compulsive disorder, started attending a mosque at Blacktown in Sydney's west just prior to going berserk in the city.    While he had shouted 'Allahu Akbar' and performed an Islamic State salute before he was apprehended, Ney denied he was motivated by religious extremism and said he had pretended to be a terrorist in the hope he would be shot by police. Ms Dunn's mother Joanne delivered a victim impact statement in which she said media coverage of her daughter's murder had 'stripped her of her identity.'  'They had no idea of the amazing woman she was,' Mrs Dunn told Justice Johnson.  'I want people to understand that Mikki could have been their daughter… she was just the girl next door.  'It seems so wrong that the perpetrator will continue on with his life at the end of his sentence.' Ney will be eligible for parole in October 2050 when he is 52. Sorry we are not currently accepting comments on this article.