British Prime Minister David Cameron accused the BBC of changing its story about Jimmy Savile as an editor who dropped an investigation into sex abuse claims against the late star stepped aside. Peter Rippon, editor of the BBC\'s flagship current affairs programme Newsnight, became the first head to roll as a documentary aired on Monday accused the world\'s largest public broadcaster of a cover-up. The BBC said a blog by Rippon, in which he explained why a show about Savile was dropped in December last year for editorial reasons, was \"inaccurate or incomplete in some respects\" and has been corrected. Cameron said the country was \"appalled\" by the growing claims against Savile, who with his jangling jewellery and shiny tracksuits was one of British television\'s best-loved stars before his death last year aged 84. \"The nation is appalled, we\'re all appalled by the allegations of what Jimmy Savile did and they seem to get worse by the day,\" Cameron told reporters. \"The developments today are concerning because the BBC has effectively changed its story about why it dropped the Newsnight programme about Jimmy Savile.\" The prime minister added that \"serious questions\" need to be answered by the two independent inquiries that the BBC has launched into the allegations about Savile. British police have launched a separate criminal investigation. Later Monday, the BBC\'s own investigative programme Panorama suggested that the broadcaster had pulled the Newsnight feature after coming under pressure from senior managers, although the programme admitted it had no smoking gun. But during the show, a lawyer for Savile\'s alleged victims claimed there was evidence of a paedophile ring within the BBC during the DJ\'s 1960s and 70s heyday. The BBC was allegedly reluctant to run the Newsnight investigation because it had already scheduled tributes to Savile for the Christmas period in 2011, following his death in November that year. Rippon\'s departure -- just hours after the BBC denied a report in the Daily Mail newspaper saying he was going to go -- failed to stem the pressure on the corporation. \"The BBC has announced that Peter Rippon is stepping aside with immediate effect from his post,\" the BBC said, adding that it \"regrets\" the errors. In the corrections posted by the BBC on Monday, the broadcaster said Rippon had incorrectly said in his blog that the corporation had no evidence that anyone from a children\'s home linked to the scandal knew about the abuse. The BBC also said that while Rippon said there was no evidence that the corporation knew of Savile\'s activities at the time, there were in fact allegations of abuse on BBC premises. It also said that some alleged abuse victims interviewed by Newsnight had not spoken to police: Rippon had initially insisted that all of them had. The row is also damaging for new BBC director general George Entwistle: Monday\'s Panorama programme claimed that his accounts of why the Newsnight programme was dropped were misleading. Karin Ward, an alleged victim interviewed by Newsnight, called the decision to pull the feature \"hurtful... because someone at the top didn\'t believe me\". Entwistle is due to testify to British lawmakers on Tuesday. Former BBC director general Mark Thompson, who is due to start as CEO of the New York Times in November, may also be called to give evidence, the Daily Mail reported. The Savile scandal has snowballed since a programme by the BBC\'s commercial rival ITV aired allegations about the entertainer by a handful of women two weeks ago. Scotland Yard says it now believes there may be 200 possible victims. It has also said it is investigating suspects who are still alive. Veteran BBC foreign editor John Simpson said in an interview to be aired on the Panorama programme that the Savile claims have plunged the broadcaster into \"the worst crisis that I can remember in my nearly 50 years at the BBC.\" But the BBC has weathered storms before. In 2004 the BBC\'s then-director general and chairman both resigned after a judge-led inquiry into the death of Iraq weapons inspector David Kelly strongly criticised the BBC. It pointed to what it said were \"unfounded\" reports that the government had \"sexed-up\" its dossier on Iraq\'s arsenal.