A police investigation into corrupt payments by journalists will be extended beyond Rupert Murdoch's British newspaper business to other publishers, the detective leading the probe into a phone-hacking scandal said on Monday.
Since January last year, police have been working with Murdoch's News International, part of News Corp, to uncover wrongdoing among its staff over allegations journalists illegally accessed mobile phone voicemail messages.
That inquiry has since been expanded to look at corrupt payments to public officials and claims of computer hacking.
The scandal has shaken the British establishment, put the notoriously aggressive press in a harsh spotlight and embarrassed senior politicians including Prime Minister David Cameron over their cosy ties to Murdoch and his executives.
News International has been particularly hit by the repercussions; Murdoch abandoned a bid to acquire the whole of the lucrative pay-TV group BSkyB, which would have been the biggest deal in News Corp's history, and also closed down the 168-year-old News of the World Sunday tabloid.
On Saturday, News Corp announced Murdoch was stepping down from a string of boards overseeing his British papers, reigniting speculation they might be sold.
However, now rival tabloids could face the same scrutiny. Deputy Assistant Commissioner Sue Akers said the focus of her investigation was being extended to examine allegations against reporters at Trinity Mirror which publishes the Daily and Sunday Mirror, and Express Newspapers, which publishes the Daily and Sunday Star titles.
"Our ongoing investigation has recently revealed that in some cases where we've identified a public official who's received payments from News International, we've also established they have received payments from other newspapers," she told a public inquiry ordered by Cameron into media ethics.
Akers said their probe had discovered that a prison officer at a high security jail had been paid 35,000 pounds by News International, Trinity Mirror and Express Newspapers between April 2010 and June 2011.
Stories relating to the payments had been identified in the Mirror and Star papers, the inquiry heard, while another prison officer had received 14,000 pounds from Trinity Mirror.
Limited public interest
"The majority of these stories reveal very limited material of genuine public interest," Akers said.
About 160 officers are examining reports that journalists at the News of the World - shut by Murdoch last July - routinely hacked into the phones of hundreds of celebrities, politicians and victims of crime to generate front-page stories.
Akers said they had notified 2,615 people who might have had their phone hacked into of which 702 were likely to have been victims.
Police are also investigating illegal payments to public officials, including police officers, and whether staff hacked into computers.
The three investigations have led to more than 60 arrests including dozens of current and former journalists, some of whom held senior
positions at News International titles.
Eleven reporters, arrested over the hacking claims, are due to report to police stations on Tuesday where they may learn if they will face charges.
Akers also revealed that their inquiries had found some material held by News International titles appeared to have come from stolen mobile telephones. Detectives hoped to establish whether these were isolated incidents or "the tip of an iceberg".