Police are looking for witnesses or anyone with dash cam footage after a robbery took place in Knowle on the night of Saturday 8 August.
CCTV enquiries are also being carried out as part of the investigation.
A police spokesperson said: “At about 11pm, an argument between a woman and two men occurred outside a takeaway in Wells Road, near the junction with Broad Walk.
“One of the males got out of the car they were in and punched the woman. Cash and a mobile phone belonging to her were subsequently taken.
“The males then left the scene in the vehicle, which is believed to have been a blue BMW.
“The woman, who is in her 20s, was taken to hospital…”
Police are keen to hear from anyone who saw what happened, or may have been driving in the area and have dashcam footage showing the vehicle involved.
Anyone who can help with their enquiries should call 101 and give reference 5220178745.
Alternatively you can call Crimestoppers anonymously on 0800 555111.