A former News of the World editor has said that 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."