A murder investigation is underway after the body of a pensioner was found in the grounds of her £2 million home.
The 81-year-old, named by neighbours as Albertina Choules, is feared to have been burned, after disturbing a burglar.
It is believed she managed to dial 999 before she was dragged outside and set alight in the early hours of Wednesday morning.
When police arrived at the property in Marlow, Buckinghamshire, they were confronted by a man wielding a machete.
He assaulted a police officer, leaving him needing hospital treatment, and fled into nearby woodland.
Choules is believed to have lived alone since the death of her company director husband 10 years ago, the Bucks Free Press reports.
Neighbours told the newspaper she was a “lovely lady” who was “liked by everyone”.
Residents in four nearby homes were awoken by police who told them not to leave their properties as the suspect was still at large.
A man was later arrested on suspicion of murder. He is currently in police custody.
Senior investigating officer, Det Supt Chris Ward of the Major Crime Unit said: “We are in the process of investigating the incident and a murder investigation has been launched.
“We have also arrested a man in connection with this incident, and he has been taken into police custody.
“I would like to appeal for anyone who thinks they might have any information about this incident to get in touch with us by calling the non-emergency number 101.
“If you do not want to speak directly to the police you can contact the independent charity Crimestoppers anonymously on 0800 555 111. No personal details are taken, information is not traced or recorded and you will not go to court.”
Deputy Commander for High Wycombe Local Policing Area, Ch Insp Rebecca Mears said: “I would like to reassure the public that this is an isolated incident.
“Members of the public will see an increased police presence in the area and a number of roads have been closed while we conduct our enquiries.
“I have this morning been to Stoke Mandeville Hospital where our injured officer was taken. He has since been discharged from hospital.”