The crash happened near Woodside Academy yesterday
It reportedly happened in Grangewood Avenue, near Woodside Academy, yesterday (Tuesday, 8 December) at around 2.40pm.
The girl involved was not seriously injured, according to Essex Police.
Three mopeds are believed to have been travelling together prior to the collision and the rider who hit the girl then got on the back of another vehicle and rode off.
In a statement, the Essex Police said: “We believe the are would have been busy at this time of day and there may be people who would have filmed the incident or the aftermath on mobile phones.
“We need anyone who has any CCTV, dash cam, or mobile phone footage to come forward.”
The force added that it has liaised with Woodside Academy and would be increasing patrols in the area.
Anyone with information is asked to call Essex Police on 101, quoting incident 562 of 8 December.
Alternatively, you can call Crimestoppers anonymously on 0800 555 111.
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Tags: Grays, Thurrock, Collision, Woodside Academy