One person has been airlifted to Sunnybrook hospital following a three-vehicle collision on County Road 27 in Barrie.
Paramedics say two drivers were uninjured while the third victim, a man in his 40s, suffered serious injuries.
The collision happened at approximately 8:30 a.m. on Highway 27 between Lougheed Road and Salem Road.
The road was closed for several hours for the police investigation.
It has since reopened.