Moors Murderer Ian Brady, who tortured and killed five children with his partner Myra Hindley, has died at the age of 79.
His death, hours after he was urged to "do the right thing" and reveal where the last of his child victims is buried, means he takes some of his secrets about the horrors to his grave.
A Mersey Care NHS Foundation Trust spokesman said: "We can confirm a 79-year-old patient in long term care at Ashworth High Secure Hospital has died after becoming physically unwell."
The spokesman said Brady died at 6.03pm on Monday, but was unable to say what Brady died of, and said he had been on oxygen for a while.
Brady was not found dead in his room in the Merseyside unit, the spokesman said, but he was unable to confirm if anyone was with him when he died, adding: "Quite possibly. I don't know."
Former police officer Norman Brennan, who represented the family of victim Lesley Ann Downey, told Newsnight about the "grief and torment" he saw on the faces of her mother and father.
He told the programme: "To know that your daughter was lost, alone and murdered and then actually her death was recorded, the grief can never ever be etched from your mind.
"Those two individuals, Myra Hindley and Ian Brady, they didn't just destroy five young children's lives.
"For their relentless appeals and false hopes that they gave the families for over 50 years destroyed all of the families as well, even to this day."
The serial killer, who used the name Ian Stewart-Brady before his death, was a patient at Ashworth Hospital where he was reportedly receiving palliative care.
At a court hearing in February lawyers said he had been bedridden for the last couple of years and it was "fair to say" he was terminally ill, with emphysema among his ailments.
Brady and partner Hindley, who died in prison in 2002, tortured and murdered five children in the 1960s.
Four of the victims were buried on Saddleworth Moor in the south Pennines.
Brady was jailed for three murders in 1966 and had been at Ashworth since 1985.
He and Hindley later confessed to another two murders.
In 2013 he asked to be moved to a Scottish prison so he could not be force fed, as he could be in hospital, and where he could be allowed to die if he wishes.
His request was rejected after Ashworth medical experts said he had chronic mental illness and needed continued care in hospital.
In February he was refused permission to launch a High Court fight to have the lawyer of his choice representing him at a tribunal where the decision would be reviewed.
Terry Kilbride, whose brother John, 12, was also murdered by Brady, begged him to tell police where he dumped the body of Keith Bennett, who went missing aged 12 in 1964.
He told The Sun: "I would beg him to do the right thing on his deathbed and tell us where Keith is.
"Now is the time for him to stop playing tricks and come clean.
"If he takes it to the grave, I will feel so sorry for Keith's family.
"There will only ever be another search if there's fresh evidence. That has to come from him."
Mr Kilbride said he hopes the killer "rots in hell".
"We'll certainly celebrate his death when it comes. Good riddance," he said.
He told ITV News it was "going to feel good" to see the murderer dead, in an interview recorded on Monday before Brady's death was announced.
He said: "Good riddance that he's gone, I don't drink but I will have a pint.
"And I think that will be the opinion of most people."