Rupert Murdoch was on Tuesday attacked with a pie by a protester during a parliamentary hearing on the phone-hacking scandal.
Two-and-half-hours into the session, the intruder rose from the public area of the room and tried to hit Murdoch with the dish of white foam.
As the police moved in - watched live by millions on television - Murdoch's wife Wendi Deng, 42, leaped forward and slapped the man on the head.
The intruder, described as a comedian, was hauled away and the session took a 10-minute break.
Earlier, calling it the "most humble day" of his life, the 80-year-old Australian-born media baron defended son James, 38, and his company, News Corp, but apologised for the wrongdoing.
He said he was "shocked, appalled and ashamed" when he read two weeks ago of the case. But asked flat out if he considered himself personally responsible, he replied, "No."
"I feel people I trusted let me down, behaved disgracefully, betrayed the company and me, and it's for them to pay."
Murdoch denounced the practice of phone-hacking and paying for information, but said, "Investigative journalism does lead to a more transparent society."
The floodgates opened two weeks ago when a lawyer for the family of murdered schoolgirl Milly Dowler said Murdoch's News of The World tabloid had hacked her phone when she was missing, deleting messages and raising false hopes that she could still be alive.
The ensuing outrage prompted News Corp to close the 168-year-old paper and drop a $12-billion plan for control of pay TV operator BSkyB, and saw the arrest of Murdoch's top aide Rebekah Brooks.
Inputs from Reuters