Ontario’s police watchdog is investigating after a pedestrian was killed in a collision in Brampton on Saturday.

Peel Regional Police and Ontario Provincial Police (OPP) received reports of a crash involving a pedestrian on Highway 410 near Steeles Avenue at 6:52 a.m.

A female pedestrian was pronounced dead at the scene, Peel police said. No other details have been released at this time.

The Special Investigations Unit (SIU) has invoked its mandate and an investigation into the incident is underway. It is unclear what prompted the agency’s involvement in the case.

All southbound lanes of the highway were closed at Steeles for several hours Saturday but have since reopened.

The SIU is an independent government agency that investigates the conduct of police officers that may have resulted in death, injury or the discharge of a firearm, or led to allegations of sexual assault.