A hospital worker has been stabbed to death while on duty.
A man has been arrested on suspicion of murder following the incident at the inpatient unit of Wotton Lawn Hospital in Gloucester at around 7.30am on Wednesday morning.
Police said the woman was taken to Gloucestershire Royal Hospital but died from her injures an hour later.
The arrested man is aged in his 60s and is being held in custody, Gloucestershire police said.
A spokesman for 2gether NHS Foundation Trust described the situation as “tragic”.
He said: “During the incident a colleague was stabbed and after being attended by fellow clinicians, was taken to Gloucestershire Royal Hospital.
"It is with deep sadness that we confirm that our colleague died a short time later. Our thoughts remain with their family and friends at this extremely difficult time.
“The full facts of this sad incident are still being established and therefore it is inappropriate for us to comment further at this time.”
The spokesman was unable to confirm the role of the staff member, but it is understood the woman was not a nurse.
The 2gether website says Wotton Lawn Hospital is an 88 bed acute mental health hospital near the centre of Gloucester which provides inpatient services for the county of Gloucestershire.
The hospital has four admission wards, a nurse led psychiatric intensive care unit (PICU) and a low secure unit (LSU).
It says service users are supported by a variety of healthcare workers including nurses, doctors, psychologists, art therapists, physiotherapists, occupational and sports exercise therapists.
Additional reporting by Press Association