The body of a dedicated volunteer was discovered inside a burning car in Ringshall, near Berkhamsted.
Officers were called just before 6pm on Friday (June 26) to Beacon Road where a car was on fire.
It was first believed that the car had been abandoned and set alight but as firefighters extinguished the blaze it became apparent there was someone in the driving seat.
An inquest into the death of Joy Hammond, of Rushendon Furlong in Pitstone has been opened and adjourned.
A post mortem examination was held on Monday afternoon (June 29).
Thames Valley Police is not treating the death as suspicious but would like to speak to anyone who saw the incident.
Det Insp Dominic Williamson, from Aylesbury CID, said: "There have been reports that a white van was in the area at the time of the incident.
"I would appeal for the driver of this vehicle to come forward, as they may have information which could assist the investigation."
He can be contacted via 0845 8 505 505 or call Crimestoppers anonymously on 0800 555 111.
PAY TRIBUTE TO MRS HAMMOND BY CLICKING HERE. For full news and analysis see The Gazette.
