A rock thrower's been at it again on the Southern Expressway.
This time, the rear passenger window of a car was smashed at O'Halloran Hill, around 3.20 yesterday afternoon.
It follows an attack last Thursday when Lauren Mangelsdorf and her 2 year old son were viciously attacked by a rock thrower while driving home from Reynella.
Police are checking CCTV footage to try and catch the culprit, they're also upping patrols in the area.
The previous Labor Government offered a $50,000 reward for information leading to a conviction for rock throwing and they're calling on the Marshall Liberal Government to do the same.
They made the commitment to tender after the election.
Labor also wants the Government to immediately install grate-style fencing across overpasses along the Southern Expressway.