As it happened: Melbourne CBD horror

It was just a small bunch of white roses on top of Bourke Street's Public Purse. A gentle sign that not all was well with Melbourne this Saturday.

The art installation is a favourite landmark, a meeting place, especially if you are new to the city. A place to perch right in front of H&M and Bardot clothing stores, usually a haunt of teenage girls.

On most weekends in January, the CBD, swollen with tourists, would just be starting to come alive at 8am. People would be gathering on the steps of the stately GPO building.

Instead an eerie silence now enveloped the empty streets following the horrific events on Bourke Street on Friday.

Four people have died – a 10-year-old girl, a 25-year-old man, a 32-year-old woman and a 33-year-old man – and 30 remain in hospital after Dimitrious "Jimmy" Gargasoulas allegedly mowed down pedestrians while driving a stolen car.

Police tape blocked off large sections of the road, with police officers and cars dominating the scene. But there were the flowers.

All day the shrine kept growing. First it was the workers, stopping on their way in, pondering what could have been if they had taken a slightly different route on Friday, or had been standing at another spot.

Others left cards, portraits and soft toys. There were children holding flowers, parents with babies in prams, elderly ladies from the country, tourists, joggers – one by one they came.

Some struggled to contain their emotions and others quietly wiped away tears. A few knelt in prayer. All seemed united in grief by the sudden and senseless events of Friday afternoon.

The silence was only broken by the hourly chimes from the old GPO clock.

City worker Aida, who was waiting just metres away at the Bourke Street tram stop when the car shot by, said witnesses were too shocked to move at first.

"I had lunch with my partner, he went to his office. I was at the tram stop at the corner," she said. "I missed the first tram, I had to wait for the second one and that was the moment when that red car went for the people.

"For five, 10 minutes everybody was at a standstill. It was so shocking."

Aida came back on Saturday with two bunches of flowers, one from her and another from her two-year-old daughter.

By afternoon, the crowds were back, standing in a solemn semi-circle around the floral tributes, some sitting on the GPO steps. But missing was the usual noise and music.

Looking on was Olivia Wyatt, a barista. On Friday, she was working as usual at the Federal Coffee Palace in the GPO building when she saw the drama unfold from the corner kiosk. It was the noise that alerted her first to the trouble.

"I heard people yelling and then just the sound of impact," Ms Wyatt said. "You could hear a body hitting a car.

"And then we looked up and there is someone rolling on top being dragged halfway across Elizabeth Street as this thing kept going."

Barely 17 hours later, at 6.30am on Saturday, Ms Wyatt was back at her job. She said the business owners had been incredibly supportive and had offered time off. But she wanted to come back.

"It was a complete tragedy and heartbreaking and it made me sick to my stomach," Ms Wyatt said. "But I needed life to go on."