Two people were rushed to a trauma centre after a crash involving a TTC bus in North York Saturday morning.
Police said the incident occurred in the area of Keele Street and Sheppard Avenue West around 9:15 a.m.
The Special Investigations Unit invoked their mandate in relation to the incident, saying an OPP officer observed two vehicles travelling at high speeds westbound on Highway 401 near Leslie Street.
One of the vehicles exited at Bathurst Street, the officer followed west on Wilson Avenue and north on Keele Street to where the vehicle collided with a TTC bus, the SIU said.
A 23-year-old man and a 24-year-old woman were ejected from the vehicle and taken to hospital with serious injuries.
Police had initially said the crash involved two vehicles and a bus.
The SIU is an independent agency that investigates incidents involving police that have resulted in death, serious injury or alleged sexual assault.