A man has been arrested on suspicion of murder following the death of a pensioner at a care home.
Avon and Somerset Police said they were called to Oaktree House in Lark Road, Yate, South Gloucestershire, yesterday following reports of the sudden death of an 87-year-old woman.
Hours later, a 33-year-old man was arrested on suspicion of murder. He remains in custody.
The woman's death is being treated as a "tragic and isolated incident" and detectives are not looking for anyone else in connection with the investigation.
Police said the victim's family have been informed and are being supported by specially-trained officers.
Detective Inspector Neil Meade, from the major crime investigation team, said: "This is a tragic but isolated incident.
"Our investigation began yesterday soon after the death was reported to us and continues today.
"We have one man in custody and we're not currently looking for anyone else."
Police later said the man in custody was not an employee of Oak Tree House.
The home is run by Four Seasons Health Care, one of the UK's biggest provider of nursing homes, care homes and specialist units throughout the UK.
It is a purpose-built home providing residential and nursing care for those with and without dementia.
Four Seasons operates more than 450 homes and employs 30,000 staff across the country, caring for 20,000 residents.
A Four Seasons spokeswoman said: "This is a deeply upsetting and distressing time for the family and we will support them as much as we can.
"A resident was found dead in her room and, in line with our normal procedures in the event of a sudden death, the home manager immediately contacted the police and relevant authorities.
"It would be inappropriate for us to comment further whilst the police investigation is on going."
Forensic experts have been coming and going at the residential home today.
In a statement, South Gloucestershire Council said: "Our thoughts are with the family.
"The incident at Oak Tree House private nursing home is subject to a police investigation and while this is ongoing it would not be appropriate to comment any further at this stage."