Police said two drivers trying to reverse into car parks were involved in a minor collision outside VicRoads about 9.30am.

Detective Leading Senior Constable Brendan Pollock said the men got out of their cars and had an altercation.

A 40-year-old man then pushed the older man as he tried to walk towards the VicRoads building.

The younger man continued into VicRoads, and is not believed to have seen the older man fall to the ground.

A 72yo man has died following a road rage incident in VicRoads carpark Burwood East. 40yo man assisting police pic.twitter.com/TVoYZgWbST — Yvette Gray (@yvettegray3AW) January 27, 2015

The older man is believed to have suffered a cardiac arrest, and another person in the car park found him less than five minutes later lying unconscious near his van.

VicRoads staff performed CPR until paramedics arrived. An Ambulance Victoria spokesman said paramedics worked on him for an hour but he was unable to be revived.

Detective Leading Senior Constable Pollock said the 40-year-old had been shaken up by the incident.

Police are investigating whether the older man had been the aggressor, and are attempting to contact his next of kin.

There is no CCTV footage of the incident, but witnesses have been interviewed.

The results of the autopsy may determine whether charges are laid against the 40-year-old, but Detective Leading Senior Constable Pollock said he was just being treated as a witness at this stage.

"It's quite a tragic incident," he said.

"It's a very minor collision that's occurred, these people have worked up, and unfortunately a man's now deceased."

Police are appealing for anybody who saw the altercation in the Lakeside Drive car park to come forward.

with Tom Cowie