Media playback is unsupported on your device Media caption Newsnight reporter Liz MacKean: "I was very unhappy the story didn't run"

The Newsnight editor responsible for dropping a report into claims Jimmy Savile sexually abused people is stepping aside, the BBC has said.

Peter Rippon's move is for the duration of an inquiry into Newsnight's handling of the planned report last year.

Earlier this month, in a blog, Mr Rippon explained the editorial reasons behind his decision to axe the report.

The BBC has now issued a correction, calling the blog "inaccurate or incomplete in some respects".

The Metropolitan Police have launched a criminal inquiry into the allegations against Savile. They have described the former BBC presenter and DJ, who died in October 2011 aged 84, as a predatory sex offender.

They believe he may have sexually abused many people, including young girls, over a 40-year period, sometimes on BBC premises.

In other developments on Monday:

The Crown Prosecution Service said it investigated four potential cases of sexual assault against Jimmy Savile in 2009, not one as previously reported, yet none of the alleged victims "would support a prosecution".

A BBC Panorama programme is airing which challenges the BBC's explanation for the dropping of the Savile investigation.

In the Panorama programme, Karin Ward - a former pupil at Duncroft Approved School in Middlesex - recalls seeing singer Gary Glitter, now a convicted paedophile, having sexual intercourse with a girl from the school in Savile's BBC dressing room.

BBC director general George Entwistle will appear in front of the Commons culture committee on Tuesday. The committee's chairman, John Whittingdale, said the BBC boss had serious questions to answer over the dropped Newsnight investigation

Analysis How much trouble is the BBC in? Its world affairs editor John Simpson sparked headlines this morning when he said it was the biggest crisis he could remember in 50 years. Some thought that over the top, pointing out that the corporation lost both its chairman and director-general after the Hutton Report in 2004. But now things have got worse. The BBC has had to admit there were errors in the Newsnight editor's explanation of why he dropped its Jimmy Savile investigation. The one silver lining is that it's Panorama, one of the BBC's own news programmes, that has brought the errors to light. But that may be small comfort for George Entwistle, as he faces MPs tomorrow to explain the BBC's handling of the crisis.

Mr Entwistle has announced two BBC inquiries regarding the sex abuse claims.

The first is looking into whether there were any failings in the BBC's management of the Newsnight investigation, which was not broadcast for editorial reasons. It is being led by former head of Sky News Nick Pollard and is expected to report in December.

The second will be led by former High Court judge Dame Janet Smith and will examine the culture of the BBC during the years that Savile worked there. The results are expected in spring 2013.

In a further move, the BBC is also to appoint an independent expert to look at sexual harassment claims and practices.

'Full facts'

In a statement on Monday, the BBC issued a correction to Mr Rippon's blog.

The corrections relate to:

Claims Newsnight had no evidence that any staff from the Duncroft approved school could or should have known about allegations of abuse involving pupils

An assertion Newsnight had no evidence against the BBC - the correction states there had been some allegations of abusive conduct on BBC premises

A statement in the blog saying all the women spoken to by the programme had contacted the police independently already and that Newsnight had no new evidence against any other person that would have helped the police

The statement said: "The BBC regrets these errors and will work with the Pollard Review to assemble all relevant evidence to enable the review to determine the full facts.

Jimmy Savile was a man with a high profile public persona, built on decades of broadcasting and charitable work. He was seen as a flamboyant eccentric but is now accused of years of sexual abuse. Explore this grid to find out more about his public life

"In addition, the BBC has announced that Peter Rippon is stepping aside with immediate effect from his post while the review by Nick Pollard... into the management of Newsnight's investigation is carried out."

Prime Minister David Cameron said earlier the nation was "appalled" by the Savile allegations, adding "they seem to get worse by the day".

He went on to say he was "sure" the BBC's own reviews would answer "serious questions" over the corporation's handling of the Savile affair.

Speaking to BBC News, Panorama and Newsnight journalist John Sweeney said two major mistakes were made by the corporation at the time of the Newsnight investigation.

The first was pulling the Newsnight expose, and the second was running the Christmas tribute programme in the light of the allegations against Savile.

Mr Sweeney - who was not involved in Monday's Panorama programme - said: "There are two people involved in that mistake. Helen Boaden, head of news, and George Entwistle, now the director general...

"Those two people decided between them that it was a good thing for the tributes to go ahead... and in the light of now.. that looked like a terrible decision".

Lord Patten, chairman of the BBC Trust, said he was "deeply concerned" about the inaccuracies in Mr Rippon's account of the reasons for scrapping the Newsnight investigation.

Timeline: Savile investigations 3 Oct: ITV broadcasts a programme into Jimmy Savile abuse claims - Exposure: The Other Side of Jimmy Savile 13 Oct: BBC director general George Entwistle announces two inquiries surrounding the Savile claims - Former Sky News head Nick Pollard is leading an inquiry into the decision to drop Newsnight's report - with results expected in December - Former Court of Appeal judge Dame Janet Smith will lead another review into the culture and practices of the BBC during Savile's time at the corporation. It will begin after police indicate it can start - The Smith review will also examine if the BBC's child protection and whistleblowing policies are fit for purpose 19 Oct: Police launch a formal criminal investigation into sexual abuse involving Savile and others - following 400 lines of inquiry BBC journalist's Savile warning

A Trust spokeswoman added: "The chairman has referred two or three times to the Peter Rippon blog, which he believed on the basis of assurances at the time to be accurate.

"He is deeply concerned that this proves not now to be the case."

The spokeswoman confirmed the Pollard review would investigate "how these inaccuracies came to be in the blog along with everything else in the Newsnight investigation."

Meanwhile, the BBC Panorama programme due to be aired on Monday night challenges the BBC's explanation for the dropping of the Savile investigation.

Mr Rippon has argued he took the decision for editorial reasons because the report would have been much stronger if Newsnight could have proven some institutional failure by the police over Savile's abuse - which the programme failed to do.

But the film's producer and reporter say they had been investigating whether Jimmy Savile was a paedophile - and claim they had enough evidence and interviews for a transmission date to be set.

Panorama says it found no evidence to suggest that Mr Rippon was pressured from above to drop the report ahead of a Christmas tribute to Savile. It also says individuals named in the programme have not yet responded to the specific points raised.

One victim, Karin Ward, tells Panorama, said that Savile's dressing room was "packed" with people while Gary Glitter abused a girl.

She said Savile was present when the abuse was taking place and "laughed about it". Glitter has denied the claims.

Panorama: Jimmy Savile - What the BBC Knew, BBC One, Monday, 22 October at 22:35 BST and then available in the UK on the BBC iPlayer.