Detectives are examining an estimated 600 fresh allegations of phone hacking at Rupert Murdoch's now closed News of the World on the back of fresh evidence obtained by the London Metropolitan police from a suspect who turned informer.
This comes as the former editor of Britain's Daily Mirror tabloid was questioned by police over suspected phone hacking, a day after four journalists from the Mirror Group, including another editor, were arrested on suspicion of illegally accessing voicemail messages.
Further details on hacking at Rupert Murdoch's now defunct News of the World newspaper are expected to emerge tomorrow morning at the high court in London during a hearing relating to litigation by hacking victims against Murdoch's News International - hours before MPs are due to vote on joint Labour and Liberal Democrat amendments that would introduce a backstop law to stiffen regulation of the press.
Sources say Scotland Yard detectives believe they can identify hundreds of new phone-hacking incidents after obtaining the telephone records of an insider who is now being lined up as a crown witness. As a result of the new information, the force's Operation Weeting is recalibrating the timetable for concluding its investigation. Police now expect their work to continue into 2015.
On Friday London police said they had interviewed a 51-year-old man, reportedly former Mirror editor Richard Wallace, as the phone-hacking scandal spread beyond Murdoch's stable of papers.
"He was interviewed under caution - not arrested - in connection with the suspected conspiracy to intercept telephone voicemails at Mirror Group Newspapers," Scotland Yard said. The man was questioned at a police station in south London and later released, it added.
James Scott, the editor of weekly tabloid The People, and his deputy, Nick Buckley, were arrested in dawn raids on their homes on Thursday, along with the Sunday Mirror 's former editor, Tina Weaver, and her former deputy, Mark Thomas.
Additional reporting by Agence France-Presse