Families whose loved ones were killed in Gosport War Memorial Hospital have expressed their fury at the prospect of enduring a further wait that could last years to learn whether criminal charges are to be brought.

A fourth, full police investigation into the hundreds of deaths linked to alleged poisoning with opiate painkillers was announced on Tuesday, and relatives who gathered for the forum in Fareham questioned why arrests had still not been made 21 years later.

Asked about the emotions among families, Charles Farthing, whose step-father Brian ‘Arthur’ Cunningham died after going into Gosport with a bedsore, said: “Anger, quite frankly”.

“The next phase is to interview families, to get individual statements,” Mr Farthing told The Independent. “That’s going to take nine months, then there will be a decision whether there’s enough evidence to go through to the next phase.”

“How long is that going to take? We don’t know.”

'We demand justice': The families at the heart of Gosport scandal Show all 4 1 /4 'We demand justice': The families at the heart of Gosport scandal 'We demand justice': The families at the heart of Gosport scandal Charles Farthing's stepfather Arthur Cunningham died at Gosport. Farthing told the inquest that Arthur was 'out of this world and I thought straight away they must be killing him, because my mum had been given a syringe driver just before she died of cancer in 1989.' BRIJESH PATEL 'We demand justice': The families at the heart of Gosport scandal Maggie Ward's mum Norma Windsor died on her 69th birthday after 10 days of 'rest and recuperation' at Gosport. Ward says: 'There should be justice. We don't understand why the deaths at Gosport aren't as important as the Shipman murders.' BRIJESH PATEL 'We demand justice': The families at the heart of Gosport scandal Iain Wilson's dad Robert's last words were 'help me son, they're killing me'. Wilson says: 'Every time I'm told 'no' by the coroner or the police or the GMC, it just makes me more determined to keep searching for the truth. I have to get justice for him.' BRIJESH PATEL 'We demand justice': The families at the heart of Gosport scandal Cindy Grant (pictured here with her brother) says of her father Stan Carby's death: 'Dad was taken from us and mum died in 2007 without knowing what happened. We have to see it through for her.' BRIJESH PATEL

“We just can’t believe we will have to wait another nine months to learn whether there will be another arrest,” said Bridget Devine-Reeves, whose grandmother, Elsie Devine, died at the hospital.

“It is catastrophic, it is something I would never wish on my worst enemy – but we fight on.

“They didn’t go there to die, but they were hooked up to syringe drivers and within hours they were killed.

“So we can’t see why more time needs to be taken when the facts are clearly there and have been laid out time and time again.”

Ms Devine-Reeves added that the names of staff involved had been established in previous reviews, but some had since died without ever facing investigation.

“But it’s become bigger,” she added. “Because they committed a crime and that was covered up by the very people who should have been there to protect my grandmother, and all those other relatives.”

Last June, the Gosport Independent Inquiry determined that excessive doses of diamorphine (heroin) and other painkillers shortened the lives of 456 people, with there likely to be 200 more deaths which could not be established because medical records had been routinely destroyed.

The report found that Dr Jane Barton, a GP and clinical assistant on the wards ,had been chiefly responsible for the “culture” of prescribing.