11 May Flashing lights and sirens. If an emergency vehicle (such as an ambulance, fire engine or police car) is coming towards you or behind you, and is using sirens and/or flashing red, blue, or blue and red lights, you must pull over and, if necessary, stop and allow it to pass. Picture of flashing red lights on an. All drivers in Ontario are familiar with the emergency red flashing lights and sirens on police cars, ambulances and fire trucks. It is common knowledge that drivers are required by law to pull to the right and stop when they see or hear emergency vehicles approaching. Flashing green lights, on the other hand, aren't quite as. Non-police vehicle flashing lights, pulling over drivers: OPP. OPP. An OPP cruiser is seen in this undated image. (Dave Chidley / THE CANADIAN PRESS). CTV Kitchener Published Friday, December 1, PM EST. Two drivers have been pulled over this week by a vehicle that appeared to belong to police, but didn't.