Specialist detectives from the Metropolitan Police have discovered the existence of a secret mobile phone within News International's east London headquarters that was used in more than 1,000 incidents of illegal hacking.

The Independent has established that the phone, nicknamed "the hub", was registered to News International and located on the News of the World's news desk. Operation Weeting, the Metropolitan Police's hacking inquiry, has evidence that it was used illegally to access 1,150 numbers between 2004 and 2006.

Weeting officers regard the extensive use of the phone over two years as significant new evidence, showing that phone hacking was carried out within the paper's newsroom.

Despite detailed company logs recording every call made on the hub phone, it was left unexamined by two internal News International inquiries, which dismissed the notion that phone hacking was rife at the title.

The phone's existence has been discussed with some victims of hacking during interviews conducted by officers from the Met's specialist crime directorate, who are reinvestigating illegal activities inside Rupert Murdoch's British subsidiary.

Who sanctioned the use of this "hub" phone, who kept it hidden and who used it illegally to access voicemails has become a key focus of the Operation Weeting inquiries. Tom Rowland, a journalist and former television producer, whose phone was hacked 60 times between 2004 and 2006, and who has been given "core participant" status in the forthcoming Leveson inquiry, was told of the "NOTW hub" during an interview at Operation Weeting's headquarters in Putney, London.

Mr Rowland said: "They [Weeting detectives] showed me a phone log taken from inside News International. They said it was the 'NOTW hub' and showed a pattern of calls made to my mobile phone." The log reveals his mobile number being accessed over 60 times, with specific dates listed.

A former journalist on the NOTW confirmed the existence of the "hub phone" saying that, inside his former newspaper's offices, it was controlled by a nucleus of individuals on the newsdesk, leaving reporters to operate "like IRA cells who were assigned stories, given precise information, but never told where this information actually came from".

The former reporter claimed that the newsdesk executives at the tabloid "kept their cards close to their chests". He said reporters "would be told precisely where a person would be at a given time, so we could go and intercept, photograph and question them. That person would be surprised at how we had discovered their whereabouts. In retrospect the obvious explanation is that a voicemail was left somewhere in which the person had declared their intention to be at a specific location at a specific time." The "hub" was described by the ex-reporter as being "at the heart of the NOTW newsroom". He said that it had been used to conduct hacking "on an industrial scale".

Dates on the phone logs from NI's internal telecommunications records point to a new front in Weeting's probe into the period between 2004 and late 2006. The NOTW is known to have been phone hacking at least as early as 2002, at the time that 12-year-old Milly Dowler disappeared. The practice continued through until at least 2007 when Glenn Mulcaire, a private investigator, and the former royal correspondent, Clive Goodman, were both jailed.

Mr Rowland, a journalist and former television executive at Endemol, the producer of Big Brother, said he had first been made aware of illegal intercepts earlier this year, when his provider from 2004 to 2006, T-Mobile, told him that evidence had been passed to the Met.

The Met's discovery of covert hacking from an internal company phone could not have come at a worst time for the UK subsidiary of the Murdoch empire. James Murdoch, deputy chairman of News Corp, is facing severe criticism from the company's shareholders and is scheduled to reappear before the Commons Culture Committee investigating phone hacking on 10 November.

Last night a spokeswoman for the Metropolitan Police said the force was unable to comment. News International stated it was "continuing to cooperate fully" with the investigation.

Hacking key quotes

Les Hinton, former executive chairman of News International

Questioned in March 2007, Hinton was asked by a Commons committee whether, following a "rigorous internal inquiry" at NI, he was convinced that Clive Goodman was the only person who knew what was going on. He answered: "Yes, and I believe he was the only person."

Andy Coulson, NOTW editor (2003-07)

At the trial of former Scottish MSP Tommy Sheridan in 2010: "I don't accept there was a culture of phone hacking at the NOTW."

Rebekah Brooks, NOTW editor (2000-2003)

Following the revelations in July this year that Milly Dowler's phone had been hacked by the NOTW: "I hope you all realise it is inconceivable that I knew or worse sanctioned these appalling allegations."

James Murdoch, chairman and CEO of News Corp Europe