The minister in charge when Jimmy Savile was appointed to work at Broadmoor psychiatric hospital said she was "shocked, surprised, startled, disgusted", as details of his catalogue of abuse within the NHS was exposed.

Edwina Currie said: "I wish we had never seen hide nor hair from him", 26 years after she rubber-stamped his appointment by a civil servant to a taskforce aimed at improving the high security hospital's governance.

Her remarks came on the day that NHS investigations confirmed that Savile – already exposed for abusing children when he worked at the BBC – was an "opportunistic sexual predator" at a string of hospitals around the country.

Currie was responsible for mental health issues in 1988 when the BBC Radio 1 DJ was given a managerial role at Broadmoor at the instigation of a senior civil servant in her department, Cliff Graham. She was also supportive of Savile's promise to confront unionised prison officers about their working practices and issued a press release praising his work ending with the words "he is an amazing man and has my full confidence".

On Thursday the NHS published the findings of investigations into Savile's activities at 28 hospital trusts, which concluded that he used the NHS and his celebrity status to "exploit and abuse" vulnerable patients and staff at hospitals across the country, including Broadmoor and Leeds General Infirmary. Investigators found he even boasted about having sex with corpses, and had a well known fixation with the dead. Jeremy Hunt, the current health secretary, described the Broadmoor appointment as "indefensible" in a Commons statement, as Labour called for an independent inquiry into the television personality's relationships with politicians, including Ken Clarke, health secretary at the time.

Hunt apologised on behalf of the government and the NHS to victims, and warned that if anyone had broken the law or hospital regulations they should face full legal consequences.

Shadow health secretary Andy Burnham said Savile's Broadmoor appointment raised "serious questions about the conduct of the civil servants and ministers in the Department of Health".

Investigators found that at Leeds General Infirmary, where Savile worked as a volunteer porter, there were at least 60 victims, from five to 75 in age. Mainly teenagers at the time, they included men, women, boys and girls. Thirty-three were patients, and 19 of these were children. Three said they were raped.

Nine of the victims told a member of staff at the time, but the inquiry found no evidence that reports of abuse by Savile were communicated to senior managers.

Abuses took place on wards, in lifts, in corridors, in offices, in his mother's house and in the campervan he parked in the hospital car park. The most recent was in 2009, when Savile was 82, two years before his death.

Assaults at other hospitals included the rape of a woman in his campervan at Digby mental hospital in Exeter, the sexual assault of two others on a ward at Moss Side in Liverpool, and an incident when he jumped into bed with a 14-year-old and touched her inappropriately at St Catherines in Birkenhead.

But it was at Broadmoor, where Savile regularly watched female patients undress to bathe, that his influential position was sanctioned at the highest level when he was appointed to the task force in 1988. Of 11 reported allegations of abuse, investigators were confident of five or six, but unable to interview the remaining alleged victims, and believed the figure to be under reported. They included patients, staff and minors.

Savile's informal association with Broadmoor began in 1968 with an unofficial role in patient entertainment, but within a few years he had hospital accommodation, a car parking place and, crucially, keys allowing him access to secure areas.

In 1988 the senior civil servant in charge of mental health within the then DHSS, Cliff Graham, had formed a close working relationship with Savile and appointed him to head a task force effectively running the hospital – a decision reported to Currie, then minister for mental health issues.

Graham, who has since died, thought the DJ "a man of considerable understanding, insight and intelligence", and accompanied him to Buckingham Palace when Savile's knighthood was conferred.

Currie told the inquiry the "task force" seemed like a good idea as Savile promised to confront the Prison Officer Association (POA) about their working practices. She thought his "blackmail" approach to the POA was "a pretty classy piece of operation". She had met him, and wrote of him in a press release: "He is an amazing man and has my full confidence."

Currie told the Guardian she was only responsible for the portfolio "for around four months". Most of the revelations were completely new to her, and his abusive behaviour was hidden at the time.

But Labour MP Tom Watson said Currie and other ministers have further questions to answer about the access granted to Savile, who had senior political connections including a friendship with Margaret Thatcher.

"In her naivety, it allowed a dangerous, predatory sex abuser unfettered access to some of the most vulnerable people in the country," he said.

Investigators found the appointment enabled Savile to use his influence to appoint a close associate as general manager in charge of Broadmoor for the next eight years. He also used it to "strengthen the impression that he was close to government ministers and Department of Health officials and was therefore in a position of authority", said the report.

Rumours of Savile's inappropriate behaviour toward young women had reached Whitehall around the time of this appointment. Investigators were told that one department official in the mental health policy team in the 1980s had heard of Savile's liking for "young ladies", and the head of the team had challenged Savile for an assurance that if he were nominated for a knighthood there would be no embarrassing revelations. There was no suspicion the girls were aged below 16.

Another senior DoH official was said to have told the permanent secretary at the department, Sir Kenneth Stowe, that Savile had "got a reputation for picking up the girls. He goes around the country and it's not very nice." In Stowe's view Savile was "a man of no repute whatsoever", but "we had no indication whatsoever that he was in any way suspect of doubtful behaviour … where he was involved with the NHS," the report said. There was no evidence ministers or officials suspected allegations of sexual abuse, it said.

The current Department of Health permanent secretary, Una O'Brien, said the report made shocking reading.

"On behalf of the previous DHSS and DoH, we are deeply sorry that inadequate processes in 1988 enabled Jimmy Savile to occupy a position of authority that he used to abuse his victims at Broadmoor Hospital," she said.

Bill Kirkup, who headed the Broadmoor investigation, said the reported figures were probably an underestimate, with many victims failing to come forward: "The fact that he occupied the position in the running of the hospital and made it known to all of the staff that he had the power to hire and fire, and in many cases they had tied accommodation as well, I think it made it very difficult in that setting for anybody to challenge what he was doing."

Julian Hartley, current chief executive of the Leeds Teaching Hospitals NHS Trust, said the Leeds report "paints a grim picture of an individual with a very dark side who used his role as a volunteer and fundraiser, combined with his national fame, to mask a range of dreadful acts he perpetrated on children and adults alike over a prolonged period of time."