are already under way, looking at failures at Newsnight and allegations relating to Savile, both of which could make uncomfortable reading for senior figures.
Police have also launched a major inquiry into Savile's crimes and victims' allegations of a high-profile paedophile ring. Detectives said they had arrested their third suspect on Sunday, a man in his 70s from Cambridgeshire in central England.
Funded by an annual licence fee levied on all TV viewers, the BBC has long been resented by its commercial rivals, who argue it has an unfair advantage and distorts the market.
Murdoch's Sun tabloid gleefully reported Entwistle's departure with the headline Bye Bye Chump and Patten said News Corp and others would put the boot in, happy to deflect attention after a phone-hacking scandal put the newspaper industry under intense and painful scrutiny.
He said that one or two newspapers, Mr. Murdoch's papers would love to see the BBC lose its national status, but I think the great British public doesn't want to see that happen.
Murdoch himself was watching from afar.
BBC getting into deeper mess. After Savile scandal, now prominent news program falsely names senior pol as paedophile, he wrote on his Twitter website on Saturday.
It is not just the BBC and the likes of Entwistle and Patten who are in the spotlight.
Thompson, whom Entwistle succeeded in mid-September, has also faced questions from staff at the New York Times over whether he is still the right person to take one of the biggest jobs in American newspaper publishing.
The Murdoch-owned Sunday Times queried how Thompson could have been unaware of claims about Savile during his tenure at the BBC as he had told British lawmakers, saying his lawyers had written to the paper addressing the allegations in early September, while Thompson was still director general.