The growing phone hacking scandal surrounding Rupert Murdoch's newspapers on Friday claimed its first high-profile casualty as Rebekah Brooks, the controversial chief executive of his British media group News International, was forced to resign despite his personal backing.

In another damage-limitation exercise, Mr. Murdoch issued a public apology for “the serious wrongdoing that occurred''.

The apology, which will be published in all national newspapers, said: “We are deeply sorry for the hurt suffered by the individuals affected. We regret not acting faster to sort things out.”

Ms. Brooks' surprise resignation came after investors warned that her continued presence was becoming a liability for the company with Prince al-Waleed bin Talal al saud, the second biggest shareholder in Mr. Mudoch's News Corporation, telling the BBC: “I will not accept to deal with a company that has a lady or a man that has any sliver of doubts on her or his integrity.''

Ms. Brooks said she felt a “deep responsibility for the people we have hurt” but insisted that she was not aware of any wrongdoing under her watch.

She was Editor of the defunct News of the World (NoW) when phones of hundreds of people, including that of a murdered teenaged schoolgirl, were hacked by its journalists for stories.

Ms. Brooks said she was resigning because she had become “focal point of the debate” which was distracting from efforts to “fix the problems of the past''.

“My resignation makes it possible for me to have the freedom and the time to give my full cooperation to all the current and future inquiries,'' she said.

Besides an ongoing police investigation, Prime Minister David Cameron has ordered a judicial inquiry into the scandal.

The House of Commons media committee has launched a separate probe and summoned Ms. Brooks, Mr. Murdoch and his son James, chairman of NI, to appear before it next week

The committee chairman John Whittingdale said her resignation was “inevitable” while Mr. Cameron described it as the “right decision''. Former NoW staff who have lost their jobs said it had come “too late''.

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