The incident happened at the pelican crossing in Cavendish Way shortly before 1pm. A pedestrian and a black Toyota Prius were involved. Officers immediately attended the scene but the vehicle was not there upon arrival.
The pedestrian, a woman, sustained serious injuries and was taken to hospital.
PC Chris Giles said: “I am appealing for information and witnesses and I am particularly keen to trace the driver of the vehicle involved. Please do come forward so we can establish what happened.
“If you were driving in the area around the time of the incident and you have a dash cam fitted, please check it and let us know if you spot anything that might help our enquiries.
“You can get in touch by calling the non-emergency number 101 or email me at [email protected] quoting ISR 357 of 22 May.”
You can report information online at http://orlo.uk/MlJ6r