- A vehicle struck pedestrians at speed on packed Flinders Street in Melbourne
- The incident happened during rush hour, at 4:41pm
- The driver of the vehicle and a second man were arrested
- The driver has mental health issues and a history of drug addiction
- Police believe the second man was not involved but are still questioning him
- Police say 19 people are injured, four critical
The man arrested after he allegedly drove car into a crowd of people in Melbourne tonight is a mental health patient with a history of drug addiction, police say.
Nineteen people were injured, four critically, after the white Suzuki SUV ploughed into pedestrians crossing the road in central Melbourne at 4.41pm.
The car drove down the tram tracks and accelerated to high speed before hitting and injuring a number of pedestrians outside Melbourne's Flinders Street station, then crashed into a tram stop bollard.
Police now say they are not treating the incident as terrorism.
Commander Russell Barrett of Victoria Police said police believe the crash was deliberate but it was too early to speculate on the motivations of the driver.
The alleged driver of the vehicle and a second man were arrested at the scene.
At a joint press conference at 11.30pm NZ time, acting Police Commissioner Shane Patton said the alleged offender was a 32-year-old Australian citizen of Afghan descent.
He was arrested at the scene by an off-duty policy officer. Patton said the man resisted arrest and both he and the officer were injured and had been hospitalised.
A second man, 24, was seen filming on his phone nearby, and was searched. Police found three knives in his bag and took him into custody. Police now say it is "probable" he has no relation to the driver but he is still being interviewed.
Patton said after reviewing footage police were satisfied only one person was in the SUV, which was registered to a relative of the alleged driver.
The alleged offender was known to Victorian police over a 2010 minor assault and more recent driving offences, but was not on bail. He had a history of drug use and mental health issues, and had been undergoing treatment for mental illness, Patton said.
Police would be investigating whether he was impaired at the time of the incident.
Although no one was killed in the incident, four people had life-threatening injuries and the police homicide squad had been deployed, Patton said.
"We don't at this time have any evidence or any intelligence to indicate there is a connection with terrorism," Patton said.
"Having said that, we continue to support this investigation with our counterterrorism command to ensure there isn't that connection and there is no ongoing threat."
He told Melbourne residents they should continue to enjoy the festive season and attend public events as normal. Hundreds more police would be on the streets to ensure public safety.
State premier Daniel Andrews said the incident was "an act of evil and an act of cowardice".
"At a time of the year when so many families are celebrating the end to the year, doing their Christmas shopping, making plans for what ought to be a festive season, we have seen a horrific act...perpetrated against innocent bystanders.
"We are all caught up in this. We are all deeply sad and deeply wounded by this terrible, terrible act."
Andrews thanked strangers who had come to the aid of the victims, and thanked emergency services for their fast response.
Nineteen people were in four hospitals around the city, including four with life-threatening injuries, Andrews said. Among them was a pre-school aged child who suffered serious head injuries. The child was in a stable condition at Royal Children's Hospital.
Footage taken by a witness shows a man in a white shirt and blue jeans being dragged from the SUV. He appears to be unconscious and police slap his face and check his pulse before he opens his eyes.
Another witness photo shows a bearded man in a red and black chequered shirt sitting on the ground with his arms cuffed behind his back. Video shows the man speaking calmly with police.
Witnesses described horrific scenes of "people flying everywhere" as the carnage unfolded at the corner of Elizabeth Street and Flinders Street at 4.41pm this afternoon during peak hour.
Witnesses told 3AW the vehicle ran a red light before mowing into pedestrians.
Other bystanders said the vehicle made "no effort to slow down".
A witness, Sue, from Walker's Doughnuts, told 3AW's Brianna Travers: "We could hear this noise, as we looked left, we saw this white car, it just mauled everybody down. People are flying everywhere. We heard thump, thump. People are running everywhere."
Witness Lauren Lopatko tweeted: "Something just happened outside Elizabeth st tram stop outside Flinders St station. Avoid area if you can. I saw ppl screaming & smoke.
Another witness, Frank, posted "I've counted 5 cop cars and an ambo coming up the tram tracks towards Flinders along Elizabeth Street ... Make that two ambos. Beat coppers were running down on foot too. Something big defs going on but not sure what."
He then updated, saying: "I've lost count how many coppers and ambos have come past now. Standing the tram stop out front of GPO."
A crime scene has been established and all vehicular and pedestrian traffic are advised to avoid the area. Members of the public with video footage or images have been encouraged to upload them here.
Australian Prime Minister has tweeted his condolences to those affected, as has New Zealand Prime Minister Jacinda Ardern.
Today's incident has brought parts of the city to a standstill four days out from Christmas.
In January this year six people died and more than 20 were injured, when a man drove a car through Melbourne's Bourke St mall. One of those who died was a three-month old baby.
Heavy concrete bollards have since been placed at key spots around the city, including at Flinders St Station, to prevent vehicles ploughing into pedestrians on footpaths.
Witnesses have praised the response from police, who were at the scene on Flinders St within moments of the crash.
Melbourne's police force had just days ago introduced new Critical Incident Response teams, with teams of armed undercover police officers, some in unmarked vehicles, patrolling the CBD ready to respond to major incidents such as terror attacks.
Acting police commissioner Patton said officers were at the scene "within 15 seconds".
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