Heather Mills on Wednesday claimed that a journalist from the Mirror Group admitted to her that he had obtained a story about her and her former husband Sir Paul McCartney by hacking into her mobile phone messages.

Mills told BBC2's Newsnight that the unidentified journalist called her in 2001, following a row with the ex-Beatle, who was then her boyfriend, and quoted parts of a message McCartney had left on her voicemail after she had travelled to India.

According to Mills, the journalist rang her and "started quoting verbatim the messages from my machine".

She said she challenged the journalist, saying: "You've obviously hacked my phone and if you do anything with this story … I'll go to the police."

Mills said he responded: "OK, OK, yeah, we did hear it on your voice messages, I won't run it."

Nancy Dell'Olio, the former partner of Sven-Göran Eriksson, also told Newsnight that she believes the Mirror hacked the couple's voicemails.

"There were strange coincidences that made me believe it absolutely," Dell'Olio said. "How they could get hold of some information? I do know that in some particular circumstances the only person who knew was me and my ex-partner."

The Mills accusation will place the spotlight back on the Mirror's publisher, Trinity Mirror, and the paper's editor at the time, Piers Morgan. Mills told the BBC it was not Morgan who called her, but the corporation has chosen not to identify the journalist. Morgan, who now hosts a chatshow for CNN, has consistently denied hacking into phones, having any knowledge about hacking at the title, or running stories obtained by using the method.

Morgan, who was in charge of the Daily Mirror for nearly a decade until 2004, issued a statement after Mills made her claim.

Trinity Mirror owns over 200 papers including the Daily Mirror and its two national stablemates, the Sunday Mirror and the People.

previous comments about the dark arts of Fleet Street, made in print and on the airwaves, have been recycled in recent weeks as claims emerged that phone hacking was not restricted to the News of the World.

"Heather Mills has made unsubstantiated claims about a conversation she may or may not have had with a senior executive from a Trinity Mirror newspaper in 2001," Morgan said. "The BBC has confirmed to me that this executive was not employed by the Daily Mirror.

"I have no knowledge of any conversation any executive from other newspapers at Trinity Mirror may or may not have had with Heather Mills.

"What I can say and have knowledge of is that Sir Paul McCartney asserted that Heather Mills illegally intercepted his telephones, and leaked confidential material to the media. This is well documented, and was stated in their divorce case.

Further, in his judgment, The Honourable Mr. Justice Bennett wrote of Heather Mills: 'I am driven to the conclusion that much of her evidence, both written and oral, was not just inconsistent and inaccurate but also less than candid. Overall she was a less than impressive witness.'

"No doubt everyone will take this and other instances of somewhat extravagant claims by Ms Mills into account in assessing what credibility and platform her assertions are given.

"And to reiterate, I have never hacked a phone, told anyone to hack a phone, nor to my knowledge published any story obtained from the hacking of a phone."

A spokesman for Trinity Mirror said: "Trinity Mirror's position is clear: all our journalists work within the criminal law and the PCC code of conduct."

Mills was the subject of intense tabloid interest before, during and after her marriage to the former Beatle. She is considering launching legal action against the News of the World after police confirmed to her earlier this year that her mobile number and other details had been found in notebooks belonging to Glenn Mulcaire, the private investigator who worked for the News of the World.

Morgan wrote in his published diary, The Insider, that following a personal request from McCartney he pulled a story about Mills and McCartney arguing in 2001 over her decision to go to India to help the victims of an earthquake.

Newsnight also says it has established that other celebrities, including Ulrika Jonsson, believe their phones were hacked by the Daily Mirror or Sunday Mirror.

Conservative MP Therese Coffey, a member of the select committee which is investigating phone hacking, called on Morgan to return to Britain from the US to help the police with their inquiries in the light of the "very strong" new evidence.

"I just hope that the police take the evidence and go with it and if Mr Morgan wants to come back to the UK and help them with their inquiries, and I don't mean being arrested in any way, I'm sure he can add more light," she told Newsnight.

"I don't see any point in him necessarily just staying in the US and issuing statements. I think it would help everybody, including himself and this investigation, if he was able to say more about why he wrote what he did in 2006.

Asked about Mills' latest allegations, she said: "I find them very strong. Although her credibility is being attacked, and has been in the past, there is no doubt she feels her privacy was infringed."

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