Initial reports from Kharkiv, the second largest city in Ukraine, claim the car involved was an Lexus SUV.
Images taken by witnesses show a large number of police cars and at least three people lying motionless in the street.
Another picture shared on Twitter shows the smashed up Lexus stretched sideways across the road.
Local media is reporting the car collided with a Volkswagen Touareg in Sumskaya Street, lost control and span into crowds walking along the pavement.
A woman has been arrested on suspicion of violating traffic safety rules, Stud Media reported.
More to follow.