Police are appealing for information following the death of a horse rider in Potton on Friday (2 November).
The incident happened at around 4.10pm in the Hatley Road area.
The horse was seen without a rider, and a woman in her 60s was found nearby with serious injuries.
She was airlifted to Addenbrooke’s for treatment, but was sadly pronounced dead on Saturday morning.
Sergeant James Wood, from the Bedfordshire, Cambridgeshire and Hertfordshire Roads Policing Unit, said: “Our thoughts go out to the lady’s family and friends at this difficult time.
“I would like to thank all those who have already come forward and shared information with the police. This has been vital in our enquiries and we are continuing to work through the information.
“While we have made good progress in our investigation, we are trying to piece together exactly what happened in this tragic incident.
“There were a number of people in the area at the time, so if anyone saw or heard anything, please get in touch.”
Anyone with any information can contact us through our online reporting centre or by calling 101, quoting Op Lyreco.