Prime Minister Malcolm Turnbull has called for more bollards to be installed in Melbourne to prevent a repeat of the Bourke Street attack that killed five people last week.

“This is a very, very concerning vulnerability,” Mr Turnbull told Melbourne radio station 3AW.

“We need to be able to ensure — as much as we can — that it is not possible to get a vehicle into that place.”

Mr Turnbull said he had already discussed security improvements with Victorian Premier Daniel Andrews and Melbourne Lord Mayor Robert Doyle.

Hundreds of flowers, teddy bears laid in tribute to the Bourke St victims. Photo: Twitter.

“We have been working effectively with state and other governments to ensure that places of mass gathering are hardened and I believe more work has to be done in that area in Melbourne,” he said.

“It’s a big open city with big streets, wide footpaths, and the attack in Bourke Street is an example of a vulnerability that we have to address.”

“It is a significant issue where you have a big mall like that where it is relatively easy to get a vehicle into a place where you have a large number of people,” he said.

“When you are looking at these pedestrian areas in cities, you need to have a very hard-headed think about how you make it harder to get a vehicle in there.

Just one vehicle — it doesn’t have to be a truck — can do so much damage.”

Scenes at Flinders St station shortly before the incident

Police were in pursuit of the vehicle before the driver drove erratically around an intersection before speeding down a footpath on Bourke Street and crashing into pedestrians.

The Victorian coroner is now investigating police conduct and the decision to call off the pursuit in the city.

In 2015, Victorian police officers became subject to new restrictions on conducting pursuits following 13 deaths in five years, but they have since been amended after the change sparked outrage from the Police Association and its members.

– ABC