WATCH: Melbourne Attack – CCTV footage of pedestrians dodging car attack.
CCTV footage shows pedestrians jump away to avoid the 'Allahu Akbar' car attack.
Four people are dead after a driver with a history of violence and drug and mental health issues mowed down pedestrians in Melbourne's CBD, ending a crime rampage of almost 12 hours.
A 10-year-old child and a man and a woman in their 30s were among those killed, while police announced a fourth person died at around 9pm on Friday night.
Five people had been in a critical condition, including a three-month-old baby and children aged two, nine and 12.
More than 20 people in total were injured in the attacks, which police say are not terror-related.
Dimitrious 'Jimmy' Gargasoulas' crime spree began about 2am and ended just before 2pm when police fired several shots, wounding the 26-year-old in the arm, and his car crashed.
Gargasoulas was under police guard in hospital on Friday night.
Police commissioner Graham Ashton said Gargasoulas was well known to police, particularly in recent days in relation to assaults, and was charged last weekend.
'What we do know of the person is there is an extensive family violence history involved,' Mr Ashton told reporters.
'We have mental health and drug-related issues in the background of this particular person.
'He has been coming to our attention more recently over recent days in relation to assaults, family violence-related assaults.
' Amid the carnage on Bourke St was half a mangled pram stuck on the bonnet of the car.
What appeared to be the other half of the pram lay on the ground at a pedestrian crossing about 100 metres up the road.
Former Victorian police chief Christine Nixon was in Bourke St and was almost hit by the car and, after seeing the pram on the ground, helped the distraught mother nearby who could not find her child.
'She kept asking me 'where's the baby?',' Ms Nixon told ABC 774.
Police believe Gargasoulas had been on a criminal rampage since about 2am, when he is accused of critically stabbing his brother outside their public housing flat in Windsor.
Mr Ashton said police made several attempts to arrest him throughout the day, but the 26-year-old kept evading them on his erratic journey across town and back.
45am police armed with guns and tasers tried to pull him over on the Bolte Bridge but aborted their pursuit because his driving was too dangerous.
Police say a woman, who may have been hostage in Gargasoulas', jumped out of the moving vehicle.
Gargasoulas was next spotted doing burnouts and screaming out his car window at terrified bystanders outside Flinders Street Station at around 1.
He then headed down Swanston St and turned left into Bourke St where he began mowing people down in the pedestrian mall.
The three dead were each found at separate locations along Bourke Street, Mr Ashton said, suggesting they weren't related.
He was eventually hit in the arm by shots police fired at him before his car crashed and he was arrested.
He was seen lying on the ground dressed only in red underwear and white shoes with several police offices standing over him.
'There's someone on the middle of the ground and there's blood all over the street,' Rishi Hathiramani, a CBD shopkeeper, told AAP.
Some CBD businesses went into lockdown, while others were evacuated.
City office worker William Mulholland said he came out of a laneway and saw a number of bodies lying on the pavement receiving CPR from police and emergency workers.
He said his friend came out of the RACV building on Bourke St and saw a body lying on the pavement in front of him.
Victims were also taken to The Royal Melbourne Hospital and The Alfred hospital Other people have also gone to hospitals in shock after witnessing the incident, police said.
Prime minister Malcolm Turnbull tweeted his sympathy.
'Our prayers and deepest sympathy are with the victims their families, of this vicious criminal attack in Bourke St Melbourne,' he tweeted.