A total of 24 suspects have now been identified by police investigating the deaths of hundreds of patients at scandal-hit Gosport War Memorial Hospital as case files have started to be sent to the Crown Prosecution Service.

An independent police investigation was launched into the community hospital in Hampshire after a probe found that hundreds of patients had their lives shortened through the use of opioids.

In 2018, the Gosport Independent Panel report concluded that the lives of more than 450 people had been shortened because of the routine practice of prescribing and administering opioids until the year 2000, and that probably at least another 200 patients were similarly affected.

The Kent and Essex Serious Crime Directorate, which is managing the investigation, codenamed Operation Magenta, has said it is reviewing the records of more than 750 patients and taken 1,200 witness statements.

The force has now confirmed that the number of suspects being interviewed has risen to 24, made up of 21 for alleged gross negligence manslaughter and three for alleged offences under the Health and Safety at Work Act.

Deputy Chief Constable Neil Jerome of Operation Magenta said: “The independent investigation into deaths at Gosport War Memorial Hospital, Hampshire, between 1987 and 2001 is one of the largest and most complex of its nature in the history of UK policing.

“Our team consists of serving and retired detectives who have so far assessed more than three million pages of documents including the medical records of over 750 patients, and taken around 1,200 witness statements from affected family members.

“Our inquiries remain ongoing and we have now reached the stage where we have started to submit case files in relation to individual patients to the Crown Prosecution Service.

“It will be the CPS’ decision as to whether or not any criminal charges are brought in relation to these cases.

“The families of those who died at the hospital were informed at the start of the investigation that the full range of criminal offences would be considered.

“The total number of suspects identified to date is 24, including 21 for alleged gross negligence manslaughter and three for alleged offences under the Health and Safety at Work Act.

“Interviews are being carried out under caution and there have been no arrests to date.

“Whilst we have never provided anyone with an estimate of how long our enquiries will last, family members and the general public can be confident we are working as quickly and thoroughly as possible to ensure Operation Magenta is the decisive police investigation into the deaths at Gosport War Memorial Hospital.”

Last year, the High Court agreed with requests by the families of Gladys Richards, Arthur Cunningham and Robert Wilson for new inquests to be held into their deaths.

Inquests were originally held into Ms Richards’s death in April 2013 and into Mr Cunningham and Mr Wilson’s deaths in March and April 2009.

The 2018 report said there was “a disregard for human life and a culture of shortening lives of a large number of patients” at the hospital.

It stated there was an “institutionalised regime of prescribing and administering ‘dangerous doses’ of a hazardous combination of medication not clinically indicated or justified”.

The inquiry, led by the former bishop of Liverpool James Jones, did not ascribe criminal or civil liability for the deaths.

The families say repeated ineffective investigations into hundreds of deaths at the hospital have left them without any justice or closure and have called for a new judge and jury inquest to be held rather than conducted by a coroner.

Leigh Day partner Emma Jones, who represents several of the families, said: “Our clients have shown immense patience and fortitude while Operation Magenta has been ongoing.

“They have already waited many years for answers into the deaths of their loved ones and progress in this investigation does not appear to have been fast.

“However, news that files have begun to be sent to the CPS may be some small comfort.

“The fact that after all these years the police have been able to find sufficient evidence to pass cases to the CPS for charging consideration makes one wonder how poor the initial investigations were and, if they had been completed thoroughly, whether lives might have been saved.

“We urge Kent Police to complete their investigations without further delay so that inquests into unexplained deaths at Gosport War Memorial Hospital can be reopened as soon as possible.

“Once more we repeat the call for a Hillsborough-style inquest into those deaths, so that families can find the answers they deserve as efficiently as possible.”