Car window shattered in Vic road rage

A man fired a gun through the back window of a car in a terrifying suspected road rage attack in Victoria.

A couple were driving through Healesville on the outskirts of Melbourne at 9pm on Sunday when a 4WD travelling behind them flashed its lights at them to speed up.

After a slow car in front of them turned off they did increase their speed but it apparently wasn't enough for the driver behind them who shattered their back window with a gunshot.

The terrified pair turned off into a supermarket car park and called the police, who arrested a 44-year-old Castella man.