Metropolitan police commander Peter Spindler discusses the report into former BBC presenter Jimmy Savile's alleged sexual offences ITN

Jimmy Savile abused children across six decades at 14 hospitals including Great Ormond Street and a children's hospice, according to a police report. He also carried out 14 alleged assaults at schools.

Commander Peter Spindler of the Metropolitan police said Savile used his fame and celebrity status to "hide in plain sight", adding that he had "groomed the nation".

The report into his activities reveals his offending spans from 1955-2009. Most of his victims were children – 73% – and he committed most of the offences when he was aged between 40 and 50.

Spindler said the report "paints a stark picture emphasising the tragic consequences of when vulnerability and power collide. His offending footprint was vast, predatory and opportunistic".

Some of the hospitals where the TV and radio presenter abused children are: Leeds general infirmary, Great Ormond Street, Exeter hospital, Saxondale mental health hospital in Nottinghamshire, and Wheatfield hospice in Leeds, a Sue Ryder hospice for dying children.

According to the report, called Giving Victims a Voice, 450 victims have come forward to allege incidents, and Savile committed 214 criminal offences in 28 areas of England and Wales.

Savile offended while working at the BBC between 1965 and 2006, the year he sexually assaulted a teenage girl at the final recording of Top of the Pops. Most of the victims were aged between 13 and 16.

Savile raped 34 people, including 28 children. He used every opportunity and every institution to which he had access because of his fame to target young people.

Fifty-seven of the allegations took place in 14 hospitals and a hospice in the UK. He assaulted 16 victims at Leeds general infirmary, one at Great Ormond Street hospital and he assaulted someone who was visiting a dying child at the Sue Ryder Wheatfield hospice in Leeds. At Great Ormond Street the child Savile abused died, but someone who witnessed what happened came forward.

He also assaulted children and young girls 33 times in TV and radio studios and there were 14 assaults in schools. Savile was invited into the schools – which have not been named – by children who wanted to appear on Jim'll Fix It, police said.

The youngest of Savile's victims was an eight-year-old boy who he touched sexually, and his last victim was a 46-year-old woman who was assaulted in 2009.

DS David Gray, who led the inquiry, said: "He has spent every minute of every working day thinking about this. Whenever an opportunity came along he took it. He picked on vulnerable victims and he was clever enough to choose people who he knew would not speak out."

Gray said he expected the number of crimes recorded to rise above 214.

The Crown Prosecution Service said in a separate report released on Friday that had police and prosecutors taken a different view to allegations from four women as recently as 2007 Savile may have been brought to justice.

The director of public prosecutions, Kier Starmer QC, issued a statement on Savile's offending. He said the report by Alison Levitt QC on the CPS's handling of cases brought before it had concluded the investigations into four complaints from women by Surrey and Sussex police could have been dealt with differently.

"Whilst most of the complainants continue to speak warmly of the individual officers with whom they had contact, most of those spoken to by Ms Levitt QC have said that, had they been given more information by the police at the time of the investigation, and in particular had each been told that she was not the only woman to have complained, they would probably have been prepared to give evidence.

"Having spoken to the complainants, Ms Levitt QC has concluded that, although there are a number of imponderables, had the police and prosecutors taken a different approach a prosecution might have been possible in relation to three of the four allegations."

The CPS review revealed how Savile had batted away the allegations made by four women in 2007-08 of past abuse. He told Surrey police in 2009 that the sexual assault complaints against him were "invented" and an "occupational hazard" for a famous entertainer.

Savile made the comments when he was interviewed under caution. He told police he had a "policy" for dealing with sexual assault complaints made against him and that he had sued five newspapers in the past. A police log of the interview records Savile as saying: "If this [these allegations] does not disappear then my policy will swing into action."

His offending took place predominantly in Leeds and London, his home town and his main work location respectively.

Gray said Savile was not part of a paedophile ring but detectives were investigating whether he was part of a loose network of paedophiles who knew each other and took advantage of their position to sexually abuse children.

The report said the institutions and agencies that missed past opportunities to stop Savile must do all they can to ensure their procedures for safeguarding children are as robust as possible.

"Only then can the victims who have come forward be reassured that it is unlikely to happen again."

Gray said: "The offences started before he was a BBC celebrity but it seems clear that his peak offending coincided with his peak status."

He said Savile did not order victims to be silent, he just abused them then discarded them. "His force of personality was powerful. He dismissed his victims afterwards; he did what he wanted to do then just discarded them and they were too frightened to speak out."

The prime minister's spokesman said: "These are further appalling allegations. What is required is that every organisation involved has to investigate what has gone on and get to the bottom of it.

"There are a series of investigations that were already ongoing into a number of hospitals. The Department of Health had already announced that Kate Lampard QC was overseeing those and she will also report to the secretary of state on what lessons can be learnt for the health system as a whole."