News Corp Chief Executive and Chairman Rupert Murdoch appears before a parliamentary committee on phone hacking at Portcullis House in London July 19, 2011. [Photo/Agencies]

LONDON - Rupert Murdoch sparred Tuesday with a committee of lawmakers over the phone-hacking scandal that has rocked his global empire, reeling from tough questioning before recovering his composure and rebuffing his interrogators with flashes of his legendary toughness.

The elder Murdoch banged his hands on the table and said the day was the most humble of his life, becoming flustered when committee members peppered with him questions and turning to his son James for some answers.

He recovered later in a tense question-and-answer session with lawmakers, pushing back with firm denials of wrongdoing.

Murdoch, 80, said he was "shocked, appalled and ashamed" at the hacking of the phone of a murdered schoolgirl by his now-shuttered News of the World tabloid. He said he had seen no evidence that victims of the September 11, 2001 terror attack and their relatives were targeted by any of his papers, adding he didn't believe the FBI had uncovered any evidence of that in a recently launched inquiry.

Murdoch said he was not responsible for the hacking scandal, and his company was not guilty of willful blindness.

He repeatedly batted away questions about operations at the News of the World by saying he wasn't really in touch with the tabloid or didn't know what was going on there.

The value of the Murdochs' News Corp added around $1.5 billion while they were being grilled, trading 3.8 percent higher at $15.54. The stock has taken a battering over the past couple of weeks, shedding around 17 percent of its value, or around $8 billion.

Rupert Murdoch said he lost sight of News of the World because it is such a small part of his company and spoke to the editor of the paper only around once a month, talking more with the editor of the Sunday Times in Britain and the Wall Street Journal in the US.

James Murdoch apologized for the scandal, telling British lawmakers that "these actions do not live up to the standards our company aspires to."

The younger Murdoch said he was surprised and shocked that his company paid the legal fees for royal reporter Clive Goodman, who was jailed in 2007 for eavesdropping on the voicemails of royal aides.

Murdoch told he didn't realize the payments had been made to the News of the World reporter, and he was not certain who signed off on the payments.

He said the company initially did not look further into alleged phone hacking in 2007 because police had said the case was closed., but once more evidence emerged the company contacted the police and "did the right thing."

Rupert Murdoch acknowledged, however, that he did not investigate after the Murdochs' former UK newspaper chief, Rebekah Brooks, told parliament years ago that the News of the World had paid police officers for information.

Asked by lawmakers why there was no investigation, he said: "I didn't know of it."

He says the News of the World "is less than 1 percent" of his News Corp, which employs 53,000 people.

Murdoch also said he was not informed that his company had paid out big sums -- 700,000 pounds ($1.1 million) in one case -- to settle lawsuits by phone hacking victims.

James Murdoch said his father became aware of the settlement "in 2009 after a newspaper report. It was a confidential settlement. "

He said a civil case of that nature and size would be dealt with by the executives in the country involved -- in this case James Murdoch, the head of News Corp's European and Asian operations.

The elder Murdoch denied that the closure of the News of the World was motivated by financial considerations, saying he shut it because of the criminal allegations.

There has been speculation that Murdoch wanted to close the Sunday newspaper in order to merge its operations with the six-days-a-week Sun, which some have said will relaunch as a seven-day publication.

Politicians also pushed for details about the Murdochs' ties to Prime Minister David Cameron and other members of the British political establishment.

In a separate hearing, lawmakers questioned London police about reports that officers took bribes from journalists to provide inside information for tabloid scoops and to ask why the force decided to shut down an earlier phone hacking probe after charging only two people.

Detectives reopened the case earlier this year and are looking at a potential 3,700 victims.