One person is dead and another is fighting for life after a car allegedly swerved into a group of people outside a major comic convention in Melbourne.
According to police, a Toyota Echo mounted a kerb on Langs Road near the Melbourne Showgrounds just after 5pm, hitting two pedestrians, both males in their early 20s.
One, who is yet to be formally identified, died at the scene.
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The second pedestrian was taken to hospital with significant lower limb injuries, and is fighting for life.
A third person in the group was not struck, but has been taken to hospital for shock. It is understood the trio had been at the Supernova Comic Con.
Police said the car, believed to be a hire car, was travelling north when it crossed lanes and mounted the footpath.
It drove between two trees, hitting the pedestrians, before travelling an extra 120 metres.
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"They are tragic, tragic circumstances," Detective Inspector Craig McEvoy said.
"We are still yet to determine if drugs, alcohol, or speed were involved", he added, noting the circumstances were "extremely unusual".
"The vehicle has travelled a significant distance along the footpath, we will try to understand the causation of what's caused the driver to travel that distance along the footpath."
McEvoy said it wasn't clear whether the incident was intentional, but added they would be investigating all avenues, including whether drugs or alcohol were involved.
"We'll look at everything… we'll let the evidence tell us what's occurred here tonight," he said.
The driver was arrested by an off-duty police officer who received assistance from the public, McEvoy said.
"He's well known to police at this point in time," McEvoy said of the driver, adding there were "some bail concerns" he was facing.
His bail status has not been confirmed by police.
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Witness recalls moment he stopped 'erratic' driver from fleeing
Witnesses told 9News they saw a car driving "at speed" towards a group of people, describing a "chaotic situation" at the scene.
A witness named Tom said he had just left the festival with his wife when he witnessed the incident.
"I heard a screech and a guy mounted the kerb at an erratic speed, hit a couple people," he told The Age.
He said he saw the car do a u-turn and drive towards him, but it stalled, prompting him to run up to the driver to stop him from fleeing.
"He was erratic," Tom said. "I said, 'you're not going anywhere mate'."
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Tom's wife, a paramedic, worked on one victim for 20 minutes, before being relieved by responding emergency services.
"He couldn't move, but he was breathing," he said.
Local resident Fabian told The Age he was shocked by the carnage at the scene.
"I really hope whoever it is pulls through … It looked really grim," he said.
Fabian added there were traffic problems surrounding the showgrounds for years.
Police remain on the scene tonight, investigating how the collision occurred.
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