Detectives are probing whether the car which ploughed into a crowd during Liverpool's victory parade tailgated an ambulance before running down pedestrians.The city's metro mayor Steve Rotheram said the vehicle should not have been on the street and the "big question" was how the incident happened.

Detectives are probing whether the car which ploughed into a crowd during Liverpool's victory parade tailgated an ambulance before running down pedestrians.The city's metro mayor Steve Rotheram said the vehicle should not have been on the street and the "big question" was how the incident happened.