News International chief James Murdoch has rejected suggestions the company operated like the Mafia over the phone hacking scandal.
During questioning by MPs, Labour's Tom Watson suggested the UK arm of the company had a policy of "omerta" - the Mafia code of silence.
Mr Murdoch told him that was "offensive and not true".
He told the committee he was not made aware that phone hacking went beyond one rogue reporter as far back as 2008.
The clash with Mr Watson, who has pursued the company over the phone hacking scandal, came halfway through the session
'Mafia boss'
Mr Murdoch had repeatedly told the committee he had not been made aware of details suggesting phone hacking went beyond Clive Goodman - the former News of the World royal reporter jailed in 2007 - when he authorised a large out-of-court settlement to footballer's union leader Gordon Taylor in June 2008.
Mr Watson asked if he was familiar with the code of "omerta" - which he characterised as "a group of people bound together by secrecy who together pursue their group's business objectives with no regard for the law" and suggested that was "an accurate description of News International in the UK".
Mr Murdoch replied: "Absolutely not. I frankly think that is offensive and that's not true."
The Labour MP said the company was facing a series of allegations around hacking and told him: "You must be the first mafia boss in history who didn't know he was running a criminal enterprise."
Mr Murdoch said that was "inappropriate" and said while it was a "matter of great regret" that "things went wrong" at the newspaper, when evidence had come to light "we acted.. I think with great zeal and diligence to get to the bottom of issues to improve the processes to make sure they didn't happen again".
The BBC's Political Editor Nick Robinson, in the hearing, reports that a fellow MP said "oh come on" when Mr Watson made his mafia claim, whilst others on the committee sighed or "tutted".
Earlier in the hearing Mr Murdoch told the committee he had not been shown a copy of the "For Neville" email at a 10 June 2008 meeting with legal manager Tom Crone, when he agreed to increase an out-of-court offer to the footballers' union leader Gordon Taylor.
He said he was given "sufficient information to authorise the increase of the settlement offer" but "was given no more than that". He said the document was never referred to as the "for Neville" email: "The nature of the so-called 'For Neville' email... any wider spread or evidence or suspicion of wider spread of wrongdoing - none of these things were mentioned to me," he said.
Mr Murdoch said if he had known more about the email "the company would have acted differently".
'Misleading' evidence
He denied misleading the committee at a hearing in July, when he said he had not been aware of the email - which is assumed to refer to former NoW chief reporter Mr Thurlbeck and contained transcripts of private voicemail messages revealing that Gordon Taylor's phone had been hacked.
Two former NoW executives - former editor Colin Myler and former legal manager Tom Crone - have said they "did inform" Mr Murdoch of the email in 2008 when he agreed to settle the Gordon Taylor case.
Mr Murdoch told the committee on Thursday: "I believe their evidence was misleading."
Mr Watson said he had been told by Neville Thurlbeck that Mr Crone had told him he would have to show the email to Mr Murdoch - and later confirmed to Mr Thurlbeck that he had done so.
Mr Murdoch replied: "I really can't say what Mr Crone or Mr Thurlbeck may have discussed but my recollection is very clear."
MP Tom Watson: "You must be the first mafia boss in history who didn't know he was running a criminal enterprise"
He was also asked about information supplied to the committee in October by solicitors Farrer and Co, who advised News International in relation to the Gordon Taylor case, including a copy of its legal opinion to the company in June 2008.
In the document, Michael Silverleaf QC says there is "a powerful case that there is (or was) a culture of illegal information access used at NGN [News Group Newspapers] in order to produce stories for publication" and advises that a public trial would be "extremely damaging" to the company's reputation.
Mr Murdoch told MPs on Tuesday: "It was not shown to me at the time, nor was it described to me in those terms in any way."
He said "clearly" some within the company knew about the legal advice and the "for Neville" email - but "none of those things were made available or discussed with me and I was not aware of those things".
Mr Thurlbeck denies he ever saw the email, telling the BBC that he neither carried out nor commissioned hacking. He says he gave NoW managers a dossier of evidence in July 2009 to show that hacking was still a problem at the newspaper and they took no action.
He also confirmed to the BBC that he had turned down a police offer of immunity from prosecution if he provided evidence of phone hacking at the paper.
He is on police bail after being arrested in April on suspicion of unlawfully intercepting voicemail messages and has also lodged a claim for unfair dismissal against News International.
In July, the News of the World was shut down after it was found to have hacked into the voicemail messages of prominent people, including murdered teenager Milly Dowler and a number of celebrities.
James Murdoch, his father Rupert, boss of parent company News Corp, and Rebekah Brooks, former editor of the NoW, have denied knowing the full extent of the allegations until evidence in civil cases was requested in late 2010.
Since the July hearing, the Metropolitan Police have raised their estimate of people who may have had their phones hacked since 2002 to 6,000.
The row has put pressure on James Murdoch's position on the News Corp board - with nearly 35% of News Corporation investors voting against him being re-elected to the board last month.