One person has been airlifted to Toronto hospital after a collision in Caledon involving a minivan and a transport truck.
Provincial Police say the van tipped over onto the van on Heart Lake Road and Charleston Sideroad just before noon.
Peel Paramedics say a total of 6 people were injured, all of whom were in the van.
In addition to the person with life threatening injuries, 3 people suffered minor injuries, while two others were hurt, but are expected to live.
Police can't say what caused the crash, but say their investigators will be on scene for the next 3 hours.
There's no word on the identities on the people in the van.