A murder probe is under way into the death of a woman on the stroke unit at Blackpool Victoria Hospital after a police investigation into suspected poisonings on the ward uncovered "suspicious" injuries.
Three nurses have been arrested - and bailed - since the probe was launched in November last year into a series of deaths at the hospital's stroke unit.
Tests have been carried out on a number of deceased patients and police now say Valerie Kneale, 75, from Blackpool, is a suspected murder victim - and are treating the case separately.
Her funeral in November was halted as a result of the police investigation.
Police say that during the examination an unexplained injury was found. A cause of death is still to be established, however, the injury is believed to be suspicious in nature.
No arrests have been made and enquiries are on-going.
Det Chief Insp Jill Johnston, of Lancashire Police, said: “We are investigating the circumstances which led to the death of a woman in Blackpool.
“A dedicated team of detectives are working on the investigation and we are still at the early stages of gathering evidence.
“We understand this is a concerning development but I would like to reassure people we are fully committed to carrying out as thorough an investigation as possible.
“Specially trained officers are providing support to Mrs Kneale’s family and my thoughts are with them at this difficult time. They are being kept fully updated and supported throughout the investigative process.
“If you can assist our enquiries, please come forward. Any information provided to police will be treated in the strictest confidence.”
A tribute from Mrs Kneale's family issued by police reads: “We as a family are completely and utterly devastated and heartbroken to have lost Val in these circumstances.
“She was the most precious wife, mother and grandmother, our constant friend and problem solver who we will miss dearly.
“We kindly ask our privacy is respected while we continue to come to terms with our loss.”
Lancashire Police has so far refused to say how many former patients have been tested as part of the investigation.
A senior officer said the inquiry is expected to "go on for months".
The investigation has looked at the use of prescription-only pills to keep patients heavily sedated during the night.
According to the NHS, the drug in question, Zopiclone, has to be ordered by a patient’s doctor and comes in tablet or liquid form. It is routinely prescribed and, when used properly, is safe.
The original allegations were made by a whistle blower, who is also a member of staff of the 780-bed hospital.
The hospital called in the police on November 8 last year, with the first nurse arrested the day after. The three nurses have all been suspended while the police investigation is ongoing.
The nurses were originally arrested on suspicion of “administering any poison or noxious thing with the intent to injure, and ill treatment or wilful neglect”, police said.
Staff at the hospital are being informed of the latest developments in the inquiry.
Wendy Swift, Chief Executive of Blackpool Teaching Hospitals NHS Foundation Trust, said: “In November 2018 a concern was raised through the Trust’s internal safeguarding processes regarding the care of patients on the stroke unit. We responded immediately and reported the concern to the police. Since then we have been working closely with them and co-operating with their inquiries.
“As part of the investigation a number of post mortem investigations were conducted. During the course of one of these an unexplained injury was found to a 75-year-old woman. A cause of death is still to be established.
“We would like to reassure all our patients that all necessary actions to provide safe care will continue to be taken and the provision of hospital services will be uninterrupted.’’
Anyone with information can contact police on 101 quoting (0756 of February 20).
Alternatively, if you have any information which could assist the police investigation, please go to: https://mipp.police.uk
The hospital trust says if you wish to report any concerns or raise any issues to hospital staff, please contact 01253 952270 between 8.30am and 5pm.