Police begin formal investigation into Jimmy Savile sex abuse allegations after identifying more than 200 potential victims

The investigation into allegations of sexual abuse by Jimmy Savile while he was working at the BBC took another twist today. (PA)

Police have begun a formal criminal investigation into alleged child abuse by Jimmy Saville, which now includes other living people, Scotland Yard said today.

The police inquiry, known as Operation Yewtree, moved from an assessment to a criminal investigation after detectives established there are lines of inquiry involving "living people that require formal investigation".

Scotland Yard said two weeks of gathering information has involved assessing more than 400 lines of inquiry and has identified more than 200 potential victims.

The force said: "As we have said from the outset, our work was never going to take us into a police investigation into Jimmy Savile.

"What we have established in the last two weeks is that there are lines of inquiry involving living people that require formal investigation."

The operation, which was originally launched as an 'assessment' of the claims was launched after police were flooded with allegations following the broadcast of the ITV documentary.

The NSPCC today reacted to the news from police saying it is possible the former Top of the Pops presenter was "one of the most prolific sex offenders" the charity has ever come across.

Investigations into the allegations are also set to scrutinise Savile's involvement with Stoke Mandeville Hospital, Broadmoor and Leeds General Infirmary.

Dame Janet Smith, who headed the Shipman Inquiry, has been appointed to head an inquiry into Savile's time at the BBC and today Scotland Yard said they recognised "her need to progress this important work".

"We are now in a position to advise the BBC that they can ask the chair of the BBC Executive Board Dame Fiona Reynolds to begin her review to run parallel to our investigation.

"We will develop a protocol to ensure any future potential criminal action is not jeopardised."

Also today, a leaked BBC email provided another twist into the investigation into allegations of sexual abuse by Jimmy Savile.

The email, which appeared in The Times this morning, appears to cast doubt on the corporation's reasons for cancelling the screening of a Newsnight investigation into claims against the late DJ.

The BBC previously insisted that the programme was dropped for 'editorial reasons' because the claims of sexual abuse by Savile 'could not be substantiated'.

The Times claimed today that the leaked internal email raises suspicions that the Newsnight report was dropped because it clashed with Christmas tributes to the former star.

A BBC spokesman said today that the email was “simply an exchange between a junior press officer and the Newsnight producer asking for further information about the Jimmy Savile investigation”.

The email, which is dated December 7, appears to show the investigation into the allegations against Savile was already well underway, and that the BBC press office was preparing 'lines to take' to respond to any questions following broadcast.

The press officer wrote that “we may well need to do a bit of managing around this” and that “we should bear in mind how BBC complaints team respond”.

The Times claims the emails also show that the BBC was aware of the risk that questions could be raised over its own conduct in the matter; in particular why the corporation did not expose Savile as a paedophile while he was alive.

Newsnight editor Peter Rippon, who recieved the email - along with a number of other staff - had previously stated that the story the programme had been pursuing had been “weakened from a Newsnight perspective” because they had been unable to establish any “institutional failure” by the police or the Crown Prosecution Service.

The Conservative MP for Reading East, Rob Wilson, who obtained the email said today: “Newsnight editor Peter Rippon and the BBC have sought to portray that the axed Newsnight report was not an expose of Savile, but was focused on the reasons the police and the CPS dropped their investigation.

“This leaked email and the evidence from internal BBC sources casts doubt on the carefully crafted version of events posted in Peter Rippon's blog on October 2.

“We need a full explanation of why the focus of the Newsnight expose of Jimmy Savile was abruptly changed at the last minute.”