A former News of the World editor said today he feared there were "bombs under the newsroom floor" in the form of a history of illegal practices at the paper.
Colin Myler told the Leveson Inquiry into press standards he felt “discomfort” over the extent of phone hacking among the now-defunct Sunday tabloid’s journalists.
He became News of the World editor in January 2007 after Andy Coulson resigned following the jailing of the paper's royal editor Clive Goodman and private detective Glenn Mulcaire.
Mr Myler told the inquiry: “It’s fair to say that I always had some discomfort and at the time I phrased it as that I felt that there could have been bombs under the newsroom floor.
“And I didn’t know where they were and I didn’t know when they were going to go off.
“That was my own view. But trying to get the evidence or establishing the evidence that sadly the police already had was another matter.”
Mr Myler stressed that he did not believe phone hacking went on at the News of the World while he was editor.
He said he assumed that the police inquiry into the illegal interception of voicemail messages by the paper, which resulted in the convictions of Goodman and Mulcaire, had not uncovered evidence against other journalists.
Noting that detectives took away three black bin liners of material when they raided Mulcaire’s home in August 2006, he said he initially accepted the line that hacking was restricted to one “rogue reporter”.
The former editor said: "Given what I believed to be a thorough police investigation throughout that period, and the fact that the police had not interviewed any other member of staff from the News of the World other than Mr Goodman, I think that weighed heavily on my mind.
"I assumed that they would have done so if they had any kind of evidence or reason to speak to somebody else." But Mr Myler changed his view after seeing the "For Neville" email, which contained transcripts of illegally intercepted voicemail messages and was apparently destined for the News of the World's chief reporter Neville Thurlbeck.
He told the inquiry: “It (the rogue reporter defence) couldn’t be correct in as much as the ‘For Neville’ email indicated that at least another reporter had transcribed it and it named another reporter.”
Mr Myler denied the News of the World carried out a "cover-up" by paying Professional Footballers' Association chief executive Gordon Taylor £425,000 plus costs to settle his claim over the hacking of his phone by the paper.
But he accepted that the company wanted to avoid the embarrassing publicity that could have resulted if the case had gone to trial.
Robert Jay QC, counsel to the inquiry, suggested: “You mentioned the bombs under the newsroom floor, but this was creating a tendency for one or more of those bombs to explode if there were a trial.”
Mr Myler replied: “Possibly that would have been the case... The company, not unreasonably or unsurprisingly, wanted to try to get things back on track after Mr Mulcaire and Mr Goodman went to jail.
“And it was a significant process to do that. So there was no appetite to go back to that place.”
Earlier today a 37-year-old woman was arrested in connection with allegations of payments to police officers in the phone-hacking inquiry.
She is being questioned at a south London police station after officers arrested her at her Surrey home at dawn, Scotland Yard confirmed.
The seventh suspect arrested under Operation Elveden - which runs alongside the Operation Weeting hacking inquiry - is not a police officer, sources say.
Elveden was launched after officers were handed documents suggesting News International journalists made illegal payments to police officers.
PA