Vietnam veteran Gary Edwards was driving on the Western Freeway when his front windscreen shattered like it had been hit by artillery fire.
Pulling over near the Lerderderg River at Bacchus Marsh, a police officer on the phone told him to park somewhere safer.
But Mr Edwards was in shock. Somebody had dropped a big rock onto his car from the Gisborne Road overpass.
“It hit like a cannon going off,” he said.
“Driving to Melbourne, I have a tendency to look up at the bridge.
“I observed two figures who looked like adults, wearing beanies or hoodies and leaning over the rail.
“Bells started to ring, but I couldn’t move because there was traffic to the side of me and then it struck.”
Pictures of Mr Edwards’ car after the incident show extensive damage to the front windscreen.
The former Nasho, who was conscripted in a lottery draw based on his birthday in the early 1970s, had been travelling to Melbourne to attend a friend’s funeral.
He has been left shaken following the close call, which occurred about 12.45pm on Monday.
“I could have been killed,” he said.
“Others could have been killed too if I’d lost control of the car.”
In 1994, Melbourne university lecturer Dr Malcolm Goodall was killed when two boys threw a 1.7-kilogram rock from a bridge onto his vehicle along the Eastern Freeway at Fairfield.
Mr Edwards, who used to work as a tipstaff in the Melbourne courts before moving to Landsborough, was reminded of Dr Goodall’s death.
"I take a fair bit of medication because of problems after the war," he said.
"On the way home I pulled over, I thought I was having a heart attack, my anxiety went sky high."
Bacchus Marsh police have been notified of the incident.
Anyone with information about the two people on the overpass is urged to contact Crime Stoppers on 1800 333 000.
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