Former Conservative MP Louise Mensch, who was a member of the parliamentary committee investigating phone hacking, said journalists told her that the practice was "widespread" within the industry.
Ms Mensch said: "I remember during the parliamentary inquiry into hacking, I was very clear, journalists were coming to me all the time saying this was a widespread practice in Fleet Street, and the further we get into it the more true that becomes."
Earlier, it was revealed that former Daily Mirror editor Piers Morgan was questioned under caution last December about phone hacking but was not arrested.
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