Up to a dozen News International executives, including Rebekah Brooks, were told in 2006 that the Metropolitan Police had evidence that more than one News of the World journalist was implicated in the phone-hacking scandal.

New information obtained by The Independent challenges the timetable, as publicly stated by Rupert Murdoch's newspaper group, of when and how it first became aware of the extent of illegality at the now-defunct Sunday tabloid. Senior figures from NI have repeatedly stated to Parliament that the company had no significant evidence until 2008 that illegal voicemail interception went beyond the NOTW's jailed royal editor, Clive Goodman.

The new evidence, which is likely to be central to the investigations into the Murdoch empire, reveals that police informed the company two years earlier that they had uncovered strong "circumstantial evidence" implicating other journalists. A senior police officer held a meeting with Ms Brooks in the weeks after the arrest in August 2006 of Mr Goodman and the private investigator Glenn Mulcaire.

The officer who met Ms Brooks – a former editor of the NOTW who at the time was editing The Sun – told her that detectives sifting through a vast cache of documents seized from Mulcaire's south London home had uncovered evidence that Goodman was not the only individual on the paper involved in criminal activity. Information was disclosed about the nature of that evidence.

Tom Crone, News International's legal manager, contacted executives from the company in early autumn 2006 informing them of the Met's meeting with Ms Brooks. The information passed on by Mr Crone to senior NI executives states that the Met investigation had gathered substantial "circumstantial evidence" that other journalists at the NOTW were involved in hacking phones.

It has already been reported that Mulcaire was in the habit of writing the name of the NOTW journalist who commissioned him to intercept voicemails in the top corner of his notes.

It has been confirmed to The Independent that among those contacted by Mr Crone was the NOTW's then-editor Andy Coulson.

The Labour MP Tom Watson, a leading campaigner on the hacking scandal, said: "If these allegations are true, then Parliament was not given the full facts of the case when senior executives appeared before MPs.

"We also need to know who it was in the Metropolitan Police that was informing News International of the conduct of a criminal inquiry that was taking place. How could it be that NI were aware of the conduct of a police inquiry almost in real time?"

The revelation that the upper echelons of the Murdoch empire were told of police evidence in 2006 raises questions about the persistent denials by executives that they knew phone hacking was being widely practised.

In July 2008, footballers' union chief executive Gordon Taylor received a £700,000 out-of-court settlement approved by News Corp's European boss, James Murdoch, following the discovery of a damaging email which suggested that knowledge of hacking at the NOTW went beyond Goodman. The deal included a confidentiality clause which kept hidden the wider use of phone hacking inside the paper.

As recently as this month, Mr Crone insisted there was "no evidence beyond Goodman" until negotiations in 2008, when Mr Taylor's legal team produced an email intended for Neville Thurlbeck, the NOTW's chief reporter, containing transcripts of Mr Taylor's phone messages from 2005.

The 2006 meeting between Ms Brooks and the Met also raises fresh questions about the closeness of the relationship between NI and Scotland Yard, which was heavily criticised for the failure of its original investigation to uncover the wider practice of hacking inside the tabloid, and the fact that no one at the NOTW beyond Goodman was interviewed by officers.

The former NOTW editor was in charge of The Sun at the time of the encounter, meaning she would have had no direct responsibility for how the Sunday title handled its response to the arrest of Goodman on 8 August 2006.

In her appearance before the Commons Media Select Committee in July, Ms Brooks nonetheless confirmed that her role involved regular meetings with senior officers, adding that she had been informed by the Yard in 2006 that her own voicemails had been targeted by Mulcaire. It is unclear whether the information implicating named additional NOTW journalists was provided at the same meeting.

The Independent understands that Andy Hayman, then the Yard's head of counter-terrorism who was in overall charge of the original hacking inquiry, was informed of the Met's meeting with Ms Brooks and that Mr Crone had subsequently informed key NOTW executives of the force's evidence.

Mr Coulson resigned following the convictions of Goodman and Mulcaire in 2007 and was subsequently hired by David Cameron as the Conservative Party's director of communications before resigning this January.

He was arrested in July on suspicion of conspiracy to intercept voicemails and making corrupt payments to police officers. He told the Commons Media Select Committee in 2009: "During that time [as editor] I neither condoned the use of phone hacking, nor do I have any recollection of instances when phone hacking took place."

Representatives of Ms Brooks and Mr Coulson declined to comment.

A News International spokeswoman said last night: "News International continues to co-operate fully with the Metropolitan Police Service in its investigations into phone hacking and police payments. We are eager to assist it in any way possible to ensure that those responsible for criminal acts are brought to justice."

A spokeswoman for the Met said: "The new evidence provided by News International continues to be considered alongside material already in the Metropolitan Police Service's possession. At the same time, all actions and decisions taken by the previous investigation are being reviewed. It would be inappropriate to discuss any further details regarding this case at this time."

Why chronology is crucial in this scandal

The closure of the News of the World has not been enough to quell the phone hacking scandal. A public appetite, a keen public interest, knowing exactly when the illegal practices began, is still there. Questions remain of who knew and what steps were taken, if any, to deal with criminality within.

Until now there have been key disclosures that from the outside take on the appearance of code-breaking, perhaps only of interest to a new class of Murdoch Kremlinologists. But the timing of what happened within the defunct Sunday tabloid has become crucial to this Fleet Street saga.

Two documents have so far dominated the who-knew-what timeframe.

The Commons culture committee regards the "For Neville" email as crucial. NI only decided in 2008 to settle, secretly, with Gordon Taylor, the footballers union boss, when Taylor's lawyers revealed that hacking went beyond one "rogue" reporter.

Tom Crone, NI's legal manager, was colloquial in his language to parliament: "Listen, it was the reason we had to settle the case... and we had to explain the case to Mr Murdoch [James] and get his authority to settle."

A year earlier, in May 2007, Clive Goodman, out of prison, wrote to Daniel Cloke, the company's human resources head, describing "other News of the World employees as clients for [Glenn] Mulcaire's solo subversive charges".

Goodman's assertion was that hacking was a culture at the NOTW. Now, despite subsequent open verdicts on NI-ordered inquiries with limited remits, and internal probes that backed the "rogue reporter" claim, NI can no longer pretend hacking was not endemic.

Nevertheless the battle for who-knew-and-when continues. The Independent's latest revelation pushes back the previous timeline by two years. It opens up a new line of questions that will be of interest to MPs when they next speak to James Murdoch and Les Hinton, who at the time of Goodman and Mulcaire's adventures was NI's chairman.