Scotland Yard detectives are today re-examining whether a series of celebrities and other high-profile individuals - including former Deputy Prime Minister John Presscott - were victims of phone hacking after fresh evidence emerged.
According to today's Daily Mail up to 3,000 potential targets of phone-hacking by private investigator Glenn Mulcaire are to be contacted.
The Mail reported that up to 20 people, told after the original 2005 invesitigation into voicemail hacking at the News of the World there was little or no information about them, are now believed to have been targeted.
The Mail reports sources saying that a hardcore of 100 phone-hack targets are expected to be discovered.
Among the names arising in the new evidence are former deputy prime minister John Prescott who is among several potential phone-hack targets currently bringing a judicial review claim over Met Police handling of the matter.
Scotland Yard has stressed that at this time there is no evidence to suggest that voicemails were actually hacked.
Senior officers said analysis of documents seized in 2005 alongside new information has led them to take a second look at whether some people may have fallen victim to the intrusive scam.
Last month the News of the World sacked assistant editor Ian Edmondson after his name emerged in evidence during a phone-hacking privacy case brought by the actress Sienna Miller. The newspaper itself then handed over new evidence to Scotland Yard.
The Metropolitan Police confirmed it is now contacting those involved, revealing detectives have an "important and immediate" new line of inquiry to follow.
Lord Prescott was briefed by police yesterday and afterwards said the original investigation into the hacking of phones, of which he believes he was a victim, was "completely inadequate".
A Metropolitan Police spokesman said: "Having begun an analysis of the documents seized in 2005 alongside the new evidence, the team have been able to make some links not previously identified.
"As a result, the team have also identified some individuals who were previously advised that there was little or no information held by the Met relating to them within the case papers and exhibits and this is now being reviewed.
"At this stage, there is no evidence to suggest that their voice mails were hacked but this will be an important and immediate new line of inquiry.
"As a result detectives are taking urgent steps to advise them of this development at the earliest opportunity."
The Met has endured a torrent of criticism over its handling of the original case, which led to the conviction of the News of the World's royal editor Clive Goodman and private investigator Glenn Mulcaire in January 2007.
In a statement yesterday, Lord Prescott said: "I can confirm that at her request I met Deputy Assistant Commissioner Sue Akers.
"She informed me that significant new evidence relating to phone hacking and myself had been discovered and that they were investigating it.
"I think this proves my long-held belief that the original Met police investigation into Mulcaire and News International was completely inadequate and failed to follow all the evidence. I now look forward to the Met police finally uncovering the truth."
Lord Prescott was refused permission to mount a High Court challenge over the force's handling of the case earlier this week.
The peer's bid for a judicial review, which was mounted along with Labour MP Chris Bryant, former Scotland Yard deputy assistant commissioner Brian Paddick and journalist Brendan Montague, is now expected to come before a judge in open court.
All claim there were human rights breaches in the way their cases were handled.
The Met reopened an inquiry into the actions of staff at the News of the World in 2005 and 2006 almost two weeks ago after receiving "significant new information" from News International.
The decision came amid a steady flow of new revelations about the practice of intercepting the voice messages of high-profile people, including politicians, police officers and Royals, using secret industry codes.
A team of detectives at the specialist crime directorate, codenamed Operation Weeting and led by Ms Akers, is now sifting through a mass of material.
Scotland Yard revealed that 2,978 phone numbers and 91 pin codes were recovered during their initial inquiry, but said this was not evidence that their phone calls had been intercepted.
Akers said everyone who had their personal details found on the documents seized during the 2005 investigation would be contacted.
"We will build on the previous commitment to all those victims whose phones we already have reasonable evidence to believe may have been hacked by establishing or renewing contact with them," she said.
"With this new investigation we will be as open as we can be and will show them all the information we hold about them, while giving them the opportunity to tell us anything that may be of concern to them.
"In time, we will go beyond this group of individuals and make contact with everyone who had some of their personal contact details found in the documents seized in 2005.
"This will ensure all of those who have been affected in some way are made aware of the information we have found relating to them."
Akers refused to discuss any of the phone numbers involved, but said she intended to make this information public at the earliest opportunity.
She added: "This is clearly a major task with a considerable amount of work to be done which will take a significant amount of time and resources.
"We will complete this new investigation as soon as we possibly can, but I am unable to predict at this early stage as to how long it will take to complete."
Last month Ian Edmondson, head of news at News of the World, was sacked two days after evidence emerged that he was linked to the hacking of mobile phones belonging to high profile individuals.
Lord Prescott said the latest development was "very significant".
He told BBC Radio 4's Today programme: "This is a very big issue, not only for the Met but also the press.
"I want to know all those who have committed criminal acts. What happened before is they decided not to pursue action against people on whom they had evidence that criminal acts had been perpetrated.
"We have got to get a proper reform of the relations between the Metropolitan Police and the press.
"I think it is going to go a long way. It doesn't stop at the Met. I think it will go to a lot of newspapers who have been hacking people for a long time."
Speaking on BBC Breakfast, Lord Prescott claimed "hundreds" of journalists were involved in phone-hacking, and that "all" newspapers were implicated.
"The papers have been at it for years," he said, adding: "There have been hundreds of journalists hacking phones in all the newspapers."
Lord Prescott suggested that the relationship between papers owned by Rupert Murdoch and the police had hampered the original investigation into phone hacking.
He said: "Since it was a criminal act committed, why didn't the police take criminal action?
"There are a lot of questions now being asked as to why they didn't do that and that is to do with the relationship, frankly, between Murdoch press and the Met Police."