A CHILD is among those killed after a car ploughed into crowds in Melbourne's CBD with unconfirmed reports of a fourth death.
The Herald Sun has revealed the man police believe is responsible for today's atrocity is 26-year-old Dimitrious Gargasoulas.
On Saturday night, Gargasoulas was bailed by a bail justice for the assault of his mother's partner Gavin Wilson.
A man and woman aged in their 30s were also killed, while 20 people were injured when the car ploughed into crowds in Bourke St Mall.
Police shot the driver before arresting him. Homicide detectives are yet to interview the 26-year-old as he remains in custody in hospital.
Police are unclear of the man's motives but are certain it was not a terror event
Police have established a hotline for concerned friends and relatives on 1800 727 077.
Royal Children's hospital said surgeons had operated on the three-month-old infant who was in a critical condition.
A two-year-old has also been moved into the RCH's intensive care unit.
Victoria's Chief Commissioner Graham Ashton confirmed the man arrested over the incident is well-known to police.
Mr Ashton said the man had no links to terrorist activity but had an extensive criminal history linked to family violence.
"He has come to our attention on many occasions in the past," Mr Ashton said.
"That is mainly linked to drug issues and mental health problems.
"He also came into our attention in recent days in relation to assaults and was charged by us last weekend."
A Victoria Police statement said: "Police shot the man who was the sole occupant of the vehicle and he received bullet wounds."
"Police understand the incident is linked to a stabbing that took place in Windsor early this morning (20 January) involving parties known to one another."
"Following this incident, it is alleged the same man took a woman, who is known to him, hostage in his car.
"She managed to escape from the car on the Bolte Bridge earlier today."
Among the injured in hospital are a nine-year-old with limb injuries who is being treated in one of the Royal Children's Hospital's wards, while a 13-year-old is in a stable condition and a 23-year-old was treated for limb injuries.
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