Officers are appealing for witnesses and information after a cyclist was knocked over at Cooksbridge, near Lewes.
The incident happened between 2pm and 2.15pm in Beechwood Lane in the village on Saturday, October 1.
A silver or grey van or pick-up truck drove too close to a woman riding on her cycle and she was struck by the wing mirror.
The collision knocked her off her bike and she sustained a serious but not life-threatening injury.
PC Martyn Quick, from the Roads Policing Unit (RPU), investigating, said: “We are appealing to identify the driver of the grey or silver van involved in this collision.
“The driver did not stop at the scene, and we believe the area was busy with other motorists and road users at the time because the level crossing nearby was down.
“Anyone with relevant CCTV or dashcam footage of the vehicle matching the description in the area at the time is asked to come forward.”
Information can be reported to Sussex Police online, on 101, or by emailing: collision.appeal@sussex.police.uk and quote serial 1123 of October 1.
