The hunt is on for the person who threw a rock at moving vehicles in Markham, leading to a serious crash.

Aurora OPP say on Sept. 20 at about 11:40 p.m., a two-vehicle collision at the intersection of Highway 48 and Major Mackenzie Dr. sent the driver and passenger of one of the vehicles to hospital with life-threatening injuries.

Police believe a “rock was deliberately thrown at the windshield of the vehicle by a passing vehicle or person, leading to the collision.”

About an hour earlier, at 10:30 p.m., police say they “received two separate reports of rocks striking the windshields of vehicles travelling northbound on Highway 48, just north of Elgin Mills.”

Both drivers were taken to hospital with minor injuries.

OPP have released videos, asking for the public’s help in identifying the vehicles.

“The driver and/or occupants of these vehicles may possess information that could assist in the ongoing investigation,” police said on social media Thursday.

Anyone who was in the area of Highway 48 near Elgin Mills between 10:30 p.m. and 11 p.m. on Sept. 20 and saw something suspicious or has dashcam or surveillance video is asked to call Aurora OPP at 1-888-310-1122 or Crime Stoppers anonymously at 1-800-222-TIPS (8477).