From across Melbourne's busy Bourke Street, Josh Baldacchino heard a group of people shrieking as a maroon Holden careened along the footpath toward them.
"The car hit them, just like insects, thud thud thud, people were being thrown in the air," the solicitor-turned-witness told the Supreme Court on Friday of the horrifying car rampage on January 20 last year.
The driver, James Gargasoulas, had a cigarette in his mouth, both hands on the wheel and "simply looked like he was going for a regular drive", Mr Baldacchino recalled.
Gargasoulas, 28, has admitted his driving on that day caused the death or injury of 33 people but he's standing trial having pleaded not guilty to six charges of murder and 27 of reckless conduct endangering life.
Mr Baldacchino described a "surreal, stunned silence" after the impacts, followed by the sounds of people screaming in pain.
Another witness, banker Aaron Jensen, also described the "horrifying" noises made by the people he saw struck outside the RACV Club.
"I still remember it today, the sound the bodies of these people being hit and the real thudding sound that made," he said.
One man tried to do a "Superman" manoeuvre out of the path of the car but his legs were hit, sending him ricocheting over the vehicle, Mr Jensen said.
He recalled the look of desperation in the man's eyes and subsequently seeing victims on the ground not knowing if they were dead or alive.
The rampage aftermath was chaotic and even experienced detectives who arrived on the scene immediately struggled with how to react.
"It was madness," Detective Senior Constable Adam Burnett said.
The officer was just 100m behind as Gargasoulas turned into the pedestrian mall, accelerated toward people sending them running and screaming.
"I could hear screaming straight away. It was madness," he said.
Earlier he'd pursued Gargasoulas through South Melbourne, until the chase was called off over safety concerns.
Instead, he elected to covertly follow the stolen Holden Commodore.
Police had tried several times over 12 hours to arrest Gargasoulas, including at one point approaching his vehicle near the Westgate Freeway with guns drawn, but each time he drove away.
"I think from experience ... there's a danger to pedestrians if we pursue or try to block him," Det Sen Const Burnett told the jury.
"Ramming with police vehicles doesn't always have a good outcome."
But as the rampage began the message over the radio changed - "the car is hitting pedestrians, it must be stopped at all costs", he recalled.
Gargasoulas was eventually stopped in Bourke St by a combination of mechanical failure and being rammed by a police car.
Detective Senior Constable Murray Gentner talked the jury through photos taken immediately after the arrest, showing significant damage to the Holden and a baby pram wedged between the windscreen and the bonnet.
Three-month-old Zachary Matthew-Bryant died after being thrown from the pram, landing more than 60m from where it was struck.
His two-year-old sister Zara suffered serious head injuries after being dragged more than 150m before being thrown.
The trial continues.