An ambulance with a patient on board has been involved in a crash in the eastbound lanes of Highway 401 near Keele Street.
It appears a taxi hit the ambulance and continued driving just after 6:30 a.m. on Thursday.
The ambulance initially reported the incident as a hit-and-run, but Ontario provincial police are now saying it may not be.
There were no injuries reported in the crash, but the ambulance was forced to pull over onto the shoulder.
The patient on board needs critical care.
He was found non-responsive with a broken leg on the street near Islington Avenue and Rexdale Boulevard.
Another ambulance, as well as OPP vehicles have been dispatched to assist.