A nurse has been charged with murdering three female patients at a hospital in West Yorkshire.
The nurse was bailed to appear before Bingley Magistrates' Court
The nurse is understood to be 51-year-old Ann Grigg-Booth.
She has also been charged with the attempted murder of a 42-year-old man and 13 charges of administering noxious substances to other patients.
Her arrest follows an inquiry into the deaths of three women, aged 96, 75 and 67, at Airedale General Hospital in Keighley, near Bradford.
Mrs Grigg-Booth has been bailed to appear at Bingley Magistrates' Court on 12 October charged with the murders.
A police spokesman said: "In relation to this investigation, three other people were arrested earlier this year, two women both aged 52 and one man aged 56.
"Files are being sent to the Crown Prosecution Service for consideration. These three people are now on police bail."
Robert Allen, chief executive of Airedale NHS Trust, said: "The investigation began when the trust reported an incident following a routine audit at the hospital.
He continued: "We are unable to say anything further about the latest details of the police inquiry, however we have been working closely with the police throughout their investigation and will continue to do so.
"This person has not worked at Airedale General Hospital since February 2003."
Airedale General Hospital is a 600 bed facility opened in 1970 which serves an area north of Bradford.