Multiple vehicles have been damaged and two people hurt by objects believed to have been intentionally thrown from a moving pickup truck northeast of Listowel.
According to Perth OPP, officers were notified about the incident along Perth Road 164 near Perth Line 89 in the Municipality of North Perth on Tuesday.
Injuries to the two people hurt were reportedly minor.
Police have not specified what type of items were being used as projectiles.
On Friday, police issued a notice about a vehicle of interest in the case. Investigators are looking for a black Dodge Ram pickup truck. It has LED lights and a blacked-out RAM logo.
No suspects have been identified at this point.
Anyone with information about the incident is asked to call police at 1-888-310-1122 or Crime Stoppers at 1-800-222-8477 (TIPS).