A 10-year-old child has died following a head-on collision east of Perth, Ont., that involved an Ontario Provincial Police (OPP) cruiser.The crash occurred on Highway 7 between Drummond School Road and Drummond Concession 7 on Dec. 13, just before 4:30 p.m. Police say an OPP officer was on patrol in a marked cruiser when it was struck by an oncoming pick-up truck.Three people were inside the pick-up. The child was airlifted to a regional trauma centre by Air Ornge but was pronounced deceased the following day. The two other occupants remain in the hospital with serious injuries.The OPP officer involved is recovering from serious but non-life-threatening injuries.The Lanark County OPP continues to investigate the collision.Authorities are seeking public assistance; anyone with information or dashcam footage related to the incident is asked to contact them.