A protester hit Rupert Murdoch with a foam pie yesterday as the media mogul testified to British lawmakers on the phone-hacking scandal, in a bizarre finale to what he called the “most humble day of my life”.

The 80-year-old News Corporation chief’s Chinese-born wife Wendi Deng leaped up and slapped the assailant, who was dragged off by police after the attack during a parliamentary committee hearing quizzing Mr Murdoch and his son James.

The Guardian newspaper and Sky News named the attacker as a comedian called Jonnie Marbles. In a Twitter message shortly before the incident, he said: “It is a far better thing that I do now than I have ever done before #splat.”

There was no confirmation of his identity as Scotland Yard had no immediate comment.

The hearing resumed 10 minutes later, with Mr Murdoch apologising to the victims of phone hacking by the now-shuttered News of the World tabloid but denying ultimate responsibility for the scandal.

Appearing frail and at times stumbling to a halt in his testimony, he had begun by saying: “I would just like to say one sentence. This is the most humble day of my life.”

Mr Murdoch said it was “not an excuse” but that with a company of 53,000 staff to oversee he could not be held fully responsible for failing to uncover the scandal.

Asked whether “ultimately you are responsible for this whole fiasco?”, Mr Murdoch tersely replied: “No”.

When pressed over whom he blamed, Mr Murdoch said: “The people that I trusted to run it (his media empire) and then maybe the people they trusted.”

But he said he was “absolutely shocked, appalled and ashamed when I heard about the Milly Dowler case two weeks ago,” referring to a murdered teenager whose phone was allegedly hacked by News of the World. Mr Murdoch was also asked about claims the newspaper targeted the voicemails of victims of the September 11, 2001 attacks in the US, but replied: “We have seen no evidence of that at all and as far as we know the FBI haven’t either.”

At times James Murdoch, the chairman of the British newspaper operation News International, tried to step in when his father faltered on a question but was several times slapped down by lawmakers.

“I would like to say just how sorry I am and how sorry we are to particularly the victims of illegal voice mail interceptions and to their families,” the 38-year-old Mr Murdoch said.

He admitted however that News International had paid the legal fees of Glenn Mulcaire, a private investigator jailed in 2007 when the hacking at the paper was first exposed. Former News International chief executive officer Rebekah Brooks told the Commons Culture, Media and Sport Committee in the afternoon that she was repeatedly told by the News of the World that allegations of phone hacking by the paper’s journalists were untrue.

She said it was only after she saw papers lodged in a civil damages case brought by actress Sienna Miller last year that she understood how serious the situation was.

“We had been told by people at News of the World at the time – they consistently denied any of these allegations in various internal investigations,” she said.

“It was only when we saw the Sienna Miller documentation that we realised the severity of the situation.”

Like Rupert and James Murdoch, Ms Brooks began her evidence by offering her “personal apology” for what had happened at the paper.

“Clearly, what happened at the News of the World and certainly (with) the allegations of voicemail intercepts of victims of crime is pretty horrific and abhorrent,” she said.

Following her arrest on Sunday by police investigating the phone-hacking allegations, she said she was appearing with her lawyer, although she stressed she intended to be as open as possible.

“Since the Sienna Miller documents came into our possession at the end of December 2010, that was the first time the senior management of the company had seen some documentary evidence relating to a current employee,” she said.

“I think we acted quickly and decisively then, when we had that information.”The Murdochs initially refused to appear before the committee but relented after they were formally summoned.

They appeared shortly after Mr Cameron, who has faced pressure over his own close friendships with a number of Mr Murdoch’s aides including Ms Brooks, cut short a trip to Africa so he could return to address Parliament today.

In a further tragic twist, British police were investigating the unexplained death of whistleblower Sean Hoare, a former reporter at the newspaper who first implicated Mr Cameron’s ex-spokesman Andy Coulson in the scandal.