The incident happened at the roundabout between Gipsy Lane and Osbourne Road on Saturday, April 30.
The boy was crossing the road at around 3.20pm when he was hit by a car, believed to be a BMW 1 series.
It has been reported that the car briefly stopped, but then made off.
The boy suffered minor injuries.
Investigating officer PC Adam Brown said: “I am really keen to hear from anybody who witnessed the incident or events leading up to the incident, in particular the occupant of a white car who had stopped for the boy to cross the road.
“This was a busy time of day where people would have been out and about on the roads making the most of the bank holiday weekend.
“Any information you give may help us establish the circumstances surrounding the incident.
“Thankfully the child only suffered minor injuries but the outcome could have been far worse, and making off from the scene of an accident will not be accepted.”
Anyone with information is urged to call 101 quoting 0254 of 30 April.