Two officers at high-security prisons allegedly took illegal payments from journalists, a senior police officer has told the Leveson Inquiry.
Metropolitan Police Deputy Assistant Commissioner Sue Akers said that detectives had analysed the stories potentially linked to payments to the two prison officers at separate high security prisons.
The first official is accused of receiving payments from Trinity Mirror, News International and Express Newspapers between April 2010 and June 2011, totalling nearly £35,000.
It is alleged that he received additional payments on top of this, with the final payment being made in February this year.
Another prison officer at a different high security prison allegedly received payments from Trinity Mirror between February 2006 and January 2012, totalling more than £14,000, the inquiry heard.
DAC Akers said: "It's our assessment that there are reasonable grounds to suspect offences have been committed and that the majority of these stories reveal very limited material of genuine public interest."
In a statement, Nick Fullagar, director of corporate communications for Trinity Mirror, said:
Express Newspapers has not commented on the allegations.
DAC Akers also gave an update on arrests made and information gathered as part of the three investigations into phone hacking, email hacking and corrupt payments to public officials.
She said, to date:
15 current and former journalists have been arrested under Operation Weeting, the Met's probe into alleged phone hacking, 12 are on bail.
Six people, including former Sun editor Rebekah Brooks and her husband Charlie, have been charged in relation to the inquiry and will appear in court in September.
41 people have been arrested under Operation Elveden, the investigation into alleged corrupt payments to officials, including 23 former or current journalists, four police officers, nine current or former public officials and five people who allegedly acted as go-betweens.
Seven arrests have been made as part of Operation Tuleta, which is looking at allegations of computer hacking and privacy infringement.
DAC Akers also said some information obtained by News International could have come from stolen mobile phones - one that was taken in Manchester and another in London.
Detectives are looking into whether this is "the tip of the iceberg" in terms of alleged accessing of stolen mobile phones, she said.
The inquiry then heard closing submissions from Neil Garnham QC for the Metropolitan Police Service (MPS).
He said that there was no inappropriate "cosiness" or corrupt relationships between journalists and the police.
Mr Garnham admitted that the decisions not to re-open the phone hacking investigation in 2009 and 2010 were taken too hastily.
But he said that these decisions were not influenced by senior officers' relationships with News International.
In a separate development, prosecutors have said they will announce tomorrow whether they will bring charges in relation to the investigation into alleged phone hacking by journalists.
Crown Prosecution Service (CPS) legal adviser Alison Levitt QC is expected to reveal at around 11am whether anyone arrested so far under Operation Weeting will face prosecution.
Eleven current and former journalists and one non-journalist detained as part of the investigation are all due to answer police bail tomorrow.