A middle-aged hospital worker has been arrested on suspicion of murder following the death of an elderly patient.
Police are investigating whether a drugs overdose led to the death of 76-year-old James May, who was a patient at the James Paget Hospital in Gorleston, Norfolk.
May, from Great Yarmouth, died on September 20 of heart failure, a post-mortem revealed earlier this week.
Further toxicology tests will determine if he died of drugs that were administered to him.
The arrested man, who was accused of malpractice and was unnamed by police, remains in custody.
Detective chief inspector Paul Durham said: 'We are investigating an allegation that a drugs overdose was administered to a patient, leading to his death.
'We understand that this news may generate concern and it's important for us to underline that our investigation, which is still at an early stage, is based on a single report of an isolated incident and that the hospital trust is co-operating fully with the investigation.'
A statement by the James Paget University Hospitals NHS Foundation Trust said: 'The James Paget University Hospital, Gorleston has called in the police following the suspicious death of a 76 year old man.'
'This follows an allegation of medical malpractice made by a member of staff after the patient's death on Friday 20 September. This matter was investigated internally and subsequently referred to the police.'
A further comment from Christine Allen, the chief executive of the hospitals called it an 'isolated incident.'
'At this time, we believe it is an isolated incident and relates to the alleged action of a single member of staff. The member of staff against whom the allegation has been made is absent from the Trust and will not return until the investigation is completed,' she said.