News International journalists repeatedly tried to hack into the phone of former British prime minister Gordon Brown, it was reported today.
The Guardian said reporters repeatedly targeted Mr Brown, attempting to access his voicemail and obtaining information from his bank account, his legal file as well as his family's medical records.
It said it had uncovered evidence that Mr Brown was targeted during a period of more than 10 years, both as finance minister and as prime minister.
Mr Brown was repeatedly targeted by News International papers the Sun and the Sunday Times, which accessed details from his legal file, Abbey National bank account and his baby son's medical records, the Guardian and the BBC reported.
Until now, allegations of illegal reporting practices have centred on the News of the World, Rupert Murdoch's mass-selling Sunday paper. The new reports alleged that there had been similar malpractice at sister papers in the News International stable.
News International, part of Mr Murdoch's News Corp group , said in a statement that it noted the allegations made concerning Gordon Brown. "So that we can investigate matters further we ask that all information concerning these allegations is provided to us," it said.
The Guardian also reported a building society had unearthed evidence suggesting that a "blagger" acting for the Sunday Times on six occasions posed as Mr Brown and gained details from his account.
It also said Mr Brown's London lawyers had been tricked into handing over details from his file by a conman who, the Guardian said, worked for the Sunday Times.
In addition, and perhaps most damaging, a Guardian investigation found that details from Brown's infant son's medical records may have been obtained by the mass-market Sun.
The paper revealed in 2006 that Brown's son Fraser has cystic fibrosis.
In a tweet posted on Twitter this evening, Mr Brown's wife, Sarah, thanked the public for its support over the allegations which she described as "hurtful if all true."
"Thinking of other families affected who did not ask to be in public eye," she wrote.