The NSPCC believe that Jimmy Savile could be the most prolific child abuser that they have ever discovered in the United Kingdom.
Peter Watt, the NSPCC's director of child protection, said: "There's no doubt that Savile is one of the most, if not the most, prolific sex offender that we at the NSPCC have ever come across.
What you have is somebody who at his most prolific lost no opportunity to identify vulnerable victims and abuse them."
The joint BBC investigation between Panorama and The World At One, which airs today on BBC One and BBC Radio 4, asks how the DJ got so close to the heart of Britain's establishment and why in 1972 the BBC failed to take effective action that might have saved young people from abuse.
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