Staff who worked at the high-security Broadmoor Hospital during the era of Jimmy Savile's frequent visits have described him as a "psychopath" with a "liking for children".
Psychiatric nurse Richard Harrison told Channel 4 News: "I'd long considered him, as my colleagues did, as a man with a severe personality disorder and a liking for children.
Former staff nurse Bob Allen described him as "a psychopath".
Jimmy Savile regularly visited Broadmoor
He added: "A lot of the staff said he should be behind bars. We used to laugh about it in those days."
Mr Allen added he had seen Savile escort a teenage girl into a flat he had been given to use at Broadmoor.
He claims he reported the matter to his supervisor but it was not followed up.
Edwina Currie, who was health minister at the time and gave Savile his role at Broadmoor, told the programme the DJ "has something on Broadmoor staff" that ensured they wouldn't speak out.
A Tweet from Channel 4 reporter Paraic O'Brien
Currie has insisted she has "nothing to hide" over her involvement in Savile's involvement at the hospital.
She told the BBC earlier this month: "The Department of Health is currently digging them [the archives relating to the time] out...It goes back at least 25 years, even 30 years and isn't just to do with me at all.
Staff told Channel 4 that when Jimmy Savile was appointed to head up a task force at the hospital in 1988, it was as though "the lunatics had taken over the asylum."
The allegations being made against Savile have raised questions as to why victims have not come forward sooner or in greater numbers.
Broadmoor is a high-security psychiatric hospital in Berkshire
Dr Elena Martellozzo, a senior lecturer in Criminology at Middlesex University and advisor to the Metropolitan Police paedophile unit, says society was, to some extent, simply blinded by his personality and celebrity status.
She told Huffington Post UK: "I think we need to remember that Jimmy Savile was an astute sex offender. He ticks every single box, in the sense that not only did he groom those children that he abused eventually, but he groomed everybody - the whole of society."
The revelations come as it was announced Savile's £4.3million estate has been frozen.
NatWest Bank, which is acting as the Jim'll Fix It presenter's will executor and trustee, said the distribution of his assets had been put on hold because of the allegations.
NatWest said in a statement: "Given the claims raised, distribution of the estate has been put on hold."
Savile's will was written in 2006 and bequeaths his savings and other assets to 26 separate beneficiaries, according to the Financial Times (FT).
The newspaper said it had obtained a copy of the document which instructs that £20,000 in cash was to be shared between 20 of the celebrity's friends, family and neighbours.
It says a further £600,000 was to be put into a trust fund, with the interest shared between eight people.
The remainder - just under £3.7 million before expenses - was to be held by NatWest on behalf of The Jimmy Savile Charitable Trust, according to the FT.
Savile's intended individual beneficiaries include the trustees of both his charities and existing and former employees of Leeds General Infirmary and Broadmoor Hospital, the newspaper added.
Police are investigating claims that the star, who died in October last year, sexually assaulted individuals at both NHS sites.
Savile's estate was previously put on hold in July after a woman claimed to be his illegitimate daughter, the FT said.
It is believed the latest freeze may be in anticipation of legal claims for damages by Savile's alleged victims.
Scotland Yard is leading a national investigation into the television and radio star's activities. He is now believed to have been one of the UK's most prolific abusers, with about 300 possible victims.
Detectives are following 400 lines of inquiry as part of the investigation while the BBC has launched an inquiry into the culture and practices at the corporation in the era of Savile's alleged sexual abuse.
It is also looking at the decision-making process that saw a Newsnight investigation into Savile's activities shelved.