A pensioner found "brutally" murdered in her own home may have been killed by an intruder.
The body of widow Una Crown, 86, who lived alone and had no children, was discovered on the floor in her bungalow in Magazine Lane, Wisbech, Cambridgeshire, shortly after 11am on Sunday.
Detectives initially treated the death as unexplained but a post-mortem examination at Peterborough City Hospital on Tuesday night confirmed she died as a result of an assault, Cambridgeshire Police said.
Detective Chief Inspector Jon Hutchinson said: "She died as a result of a brutal assault in her own home."
Mrs Crown was last seen by family members at 11am on Friday. She made a phone call to a friend at 6pm on Saturday night and officers believe she was killed at some point overnight.
Mr Hutchinson said the case was not being linked to any other crimes in the area but said one possibility was that Mrs Crown had been killed after a suspect broke into the house. The detective said there was no evidence of a sexual assault and the property had not been ransacked.
He added: "Searches and checks are being carried out to establish whether entry was forced. It is too early to say what the motive was. This is a close-knit community and we are talking to her family and neighbours.
"Our investigation is still at a very early stage and we are trying to build up a picture of the events that led to her death. Her murder has obviously devastated her family and I would urge anyone with any information to call police."
Neighbour Maureen Lawrence said she knew Mrs Crown to say hello to in the street. She added: "I can't remember exactly when I last saw her but she had seemed normal and without any worries. When I heard she had died I presumed, because of her age, she had died peacefully but now we are hearing differently, which is very upsetting."
Anyone with any information should call the Major Crime Unit on 101 or Crimestoppers, anonymously, on 0800 555111.