Scotland Yard has confirmed that it is now running a "formal criminal investigation" into the allegations of sexual abuse against the former Jim'll Fix It star.
Following two weeks of information gathering, officers in the Operation Yewtree investigation are now pursing in excess of 400 lines of enquiry and have identified over 200 potential victims.
The head of children's charity NSPCC Peter Watt has said that Jimmy Savile may be "one of the most prolific sex offenders the NSPCC has ever come across".
The BBC has already announced investigations into allegations that Savile may have abused young girls while he worked for the corporation, but said that it would wait until given the greenlight by police.
The Metropolitan Police has now told the chair of the BBC executive board Dame Fiona Reynolds to "begin the review to run parallel to our investigation".
Copyright: flickr/BBC PicturesScotland Yard intends to develop "a protocol to ensure any future potential criminal action is not jeopardised" by the BBC investigation.
Led by former High Court judge Dame Janet Smith, the BBC's internal probe will review "the culture and practices of the BBC during the years that Jimmy Savile worked at the BBC".
It will also examine whether the BBC's child protection and whistleblowing policies are "fit for purpose".
Dame Janet will be assisted by an expert in the safeguarding of children, along with legal support independent of the BBC's management.
The BBC is also running a separate investigation into the decision to drop a Newsnight investigation into the allegations against Savile last December. This wil be led by Nick Pollard, the former head of Sky News.
> Jimmy Savile: Leaked BBC email casts doubt on Newsnight claims
There have been questions over why the investigation was dropped, particularly as tribute programmes to Savile were aired on the BBC that month and in January 2012.
The Pollard Review will "seek to establish whether there were any failings in the BBC's management of the Newsnight investigation relating to allegations of sexual abuse of children by Jimmy Savile, including the broadcast of tribute programmes on the BBC".