Police were called after masked moto bike riders were seen driving dangerously, with one carrying a child.
The riders weren't wearing helmets when they were spotted at Oldbury Court Estate, Fishponds.
They were reported to police at 4.4pm on Sunday February 9.
On arrival, witnesses told police the vehicles were driving at speed and too close to pedestrians.
A spokesperson for Avon and Somerset Constabulary said: "As we went into the car park we saw three people riding on two bikes.
"The solo rider abandoned their bike and jumped onto the other one.
All three made off on the one bike which was lost to sight. Police seized the abandoned bike.
One of the riders is described as white, in his late teens and wearing a dark-coloured tracksuit.
The spokesperson continued: "We’d like to hear from anyone with information about the riders.
"If you can help, please call 101 and give the call handler the reference number 5220032905"
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