Former prime minister Gordon Brown accused Rupert Murdoch's media empire on Tuesday of using criminals to obtain his private documents, as MPs prepared to quiz police over phone hacking.

In a major new twist in the row that led to the closure of the Murdoch-owned News of the World, Brown accused its stablemate the Sunday Times of using con tricks to obtain bank details and legal documents relating to a flat he bought.

He also said he did not understand how The Sun, another Murdoch paper, obtained information that his son had cystic fibrosis, adding that when the tabloid splashed the news on its front page in 2006 he was left "in tears".

"I think what happened pretty early on in government was that the Sunday Times appear to have got access to my building society account, they got access to my legal files," Brown told the BBC in an interview.

"But I'm shocked, I'm genuinely shocked to find that this happened because of their links with criminals, known criminals who were undertaking this activity, hired by investigators who were working with the Sunday Times."

His claims are the first to explicitly drag in other Murdoch newspapers into the long-running scandal over phone hacking at the News of the World, and threaten to further damage Murdoch's media interests.

They come as MPs prepare to question senior police officers about why their original investigation into phone hacking at the News of the World in 2006 failed to unearth the hoard of allegations that have emerged in recent months.

In the latest twist, it was reported that Prince Charles and his wife Camilla had their voicemails hacked.

Media reports also suggested that police officers charged with protecting members of the royal family had sold their details to the News of the World, and the tabloid's owners knew about this as early as 2007 but kept quiet.

The scandal prompted Murdoch to abruptly close down the 168-year-old tabloid last week, and sparked intense political pressure on his News Corp.'s controversial bid for control of satellite broadcaster BSkyB.

News Corp. on Monday announced it was withdrawing concessions which it had offered to assuage competition concerns over the bid, prompting the government to refer the bid to the Competition Commission.

Murdoch flew to London on Sunday to try to contain the crisis, and also to offer his full support to Rebekah Brooks, the chief executive of his British media interests, News International.

Brooks was editor of the News of the World from 2000 to 2003, and then moved to The Sun, but has always denied any knowledge of phone hacking.

Brown said it was Brooks who called him to tell him in 2006 that the tabloid was breaking the story about the illness of his son, who was then four months old.

"I've never talked publicly about Fraser's condition. And obviously we wanted that to be kept private for all the obvious reasons," said Brown, who was Chancellor of the Exchequer from 1997 to 2007 and then Labour prime minister until 2010.

Asked how it felt to see the news splashed over the media, he replied: "In tears. Your son is being broadcast across the media. Sarah (his wife) and I are incredibly upset about it."

Although he did not directly accuse The Sun of wrongdoing, he said he "can't think" how they would have got the medical records legitimately.

News International has asked to see the information on which Brown is basing his allegations, but a source at the group told AFP: "We are satisfied that the story about his son came from legitimate sources."

Scotland Yard launched a new investigation into phone hacking in January, and on Monday it warned that leaks to the media -- including about alleged payments to royal protection officers -- threatened to undermine its efforts.

But it is under pressure itself, and several officers were to appear before parliament's home affairs committee on Tuesday.

These included Scotland Yard Assistant Commissioner John Yates, the police officer who decided in 2009 that the original probe into phone hacking did not need to be reopened despite new revelations.

The original 2006 police investigation led to the News of the World's then royal editor and a private investigator being jailed. Many of the recent revelations stem from the files seized from the investigator during that time.