The man who allegedly mowed down 18 people in Melbourne's CBD on Friday, killing three and injuring 15 others, has a history of drug use, violence and psychological problems.
James "Jimmy" Gargasoulas, 26, lived in public housing flats in Windsor, where he allegedly stabbed his brother, Angelo, in the early hours of Friday morning.
Neighbours said they had regularly heard arguing inside the Raleigh Street unit, where the two brothers lived with their mother.
In the early hours of Friday morning, Jess Bergin said she heard screaming outside her flat on the other side of road and looked out the window.
"He had a knife and he was hacking at either a guy or a girl, I don't know," she said.
They got into a waiting a car, except for the knife-wielding man, who began hacking at the car, she said.
She said he then got in the car, but got out and started walking towards Punt Road.
Mr Gargasoulas, who also goes by the name Dimitrios, is currently on bail after being charged with family violence offences last weekend.
He is known to police for drug related issues, family violence assaults and has "an extensive family violence history".
It is understood that police began pursuing Gargasoulas earlier on Friday in a maroon-coloured sedan after he allegedly took a woman hostage, who later escaped on the Bolte Bridge.
Police called off the pursuit over concerns of public safety, just outside the CBD.
The car was next seen doing "burnouts" and driving erratically at the intersection in front of Flinders Street Station. Gargasoulas was filmed hanging out the driver's window and abusing passerby.
He then sped north towards Bourke Street, where he allegedly ploughed through the crowded shopping strip, killing three people and injuring at least 15.
Police shot Gargasoulas in the arm further west on Bourke Street, dragging him from the sedan and making an arrest. He is being treated in hospital with non-life threatening injuries.
A relative said Jimmy has had a drug problem and has been in and out of jail for car theft and drug offences.
"Jimmy has always been a bad person," she said. "I knew it was him. I saw it on TV ... the picture of him sticking his head out when he was doing burnouts.
"I saw a picture and I thought 'Oh My God, that's Jimmy.' I'm shaking. I knew it, as soon as I saw that picture I had this feeling. I can't believe this.
"I balled out crying when they announced that baby died. I'm shaking, I just can't believe this."