LONDON - The crisis rattling Rupert Murdoch’s global media empire claimed the two highest-level executives yet yesterday after days of mounting pressure from politicians and investors on two continents.

Les Hinton, publisher of The Wall Street Journal since 2007, who oversaw News International, Murdoch’s British newspaper subsidiary, when voice mail hacking by journalists was rampant, and Rebekah Brooks, who has run the British papers since 2009 and become the target of unrelenting public outrage, both resigned in the latest blow to News Corp. and its chairman.

Hinton, chief executive of Dow Jones & Co., and Brooks were two of Murdoch’s closest and most loyal deputies. He was said to be loath to lose either of them and became convinced that they had to leave only over the last several days.

The resignations came on a day when Murdoch made a series of public apologies. He wrote a letter to be published in all British newspapers this weekend acknowledging that the company did not address its problems soon enough. “We are sorry,’’ it begins.

He also visited the family of a murdered 13-year-old girl, Milly Dowler, whose voice mail was hacked by reporters at News of the World while she was still listed as missing. According to the Dowler family’s lawyer, Mark Lewis, Murdoch held his head in his hands and apologized for the actions of his employees, who deleted phone messages after the girl’s mailbox had been filled so they could collect more messages from concerned family members.

Lewis said that Murdoch apologized “many times’’ and that he was “very humbled, he was very shaken, and he was very sincere.’’

Whether these actions will do anything to quiet the backlash against News Corp. is unclear. Murdoch, Brooks, and James Murdoch, the company’s deputy chief operating officer, will testify next week before Parliament.

Brooks, who was editor of News of the World when the abuses began in 2002, repeatedly told the Murdochs that she knew nothing of the hacking and that she would be exonerated when all the facts came out.

In her farewell message, Brooks acknowledged that she had become a distraction. “As chief executive of the company, I feel a deep sense of responsibility for the people we have hurt and I want to reiterate how sorry I am for what we now know to have taken place,’’ she wrote.

Yesterday, former staff members at News of the World questioned why Brooks did not resign earlier. “Our paper was sacrificed to save her career, and now she’s gone as well,’’ one former employee said, requesting anonymity because he did not want to jeopardize his severance negotiations following the newspaper’s closure. “Who knows why they’ve chosen to do it now, as she’ll have to appear before the select committee anyway.’’

Until yesterday, Hinton had been largely an offstage figure in the scandal. But questions grew about what he knew about the improper practices going on at the newspapers under his watch, even though he has testified twice before Parliament saying that he believed the hacking was limited to one rogue journalist.

Hinton spent part of his career at the Boston Herald. He was named associate editor after Murdoch bought the paper in 1982. Hinton previously served as editor of Murdoch’s Star national weekly paper. Murdoch later sold the Herald.

Last March, Patrick J. Purcell, president and publisher of the Herald, introduced Hinton as a keynote speaker at the Boston College Chief Executives’ Club of Boston luncheon. Hinton talked about the role of newspapers and the importance of information in today’s digital age.

“Everything we know about news and information is changing - what it is, where it comes from, how we consume it, and what we can trust,’’ he said, according to BC’s website.

Letting Hinton go was an especially fraught decision for Murdoch. The two had worked together for 52 years, since Hinton joined Murdoch’s first paper, The News of Adelaide in South Australia, when he was 15; Hinton ran the Journal, Murdoch’s most cherished US newspaper.

In a note to his employees, Hinton said yesterday was “a deeply, deeply sad day for me.’’

Michael Warshaw of the Globe staff contributed to this report.

© Copyright 2011 Globe Newspaper Company.