Senior executives at the Sun newspaper who were closely associated with former News International chief executive Rebekah Brooks have been arrested on suspicion of making illegal payments to police officers.
The journalists were detained in a series of dawn raids after information was handed to Scotland Yard by News Corporation, the tabloid's parent company.
One of the arrested journalists is believed to be Fergus Shanahan, 57, who was Mrs Brooks' deputy during her editorship of the Sun from 2003 to 2009, and who now works as a comment writer.
Another executive said to have been arrested is Graham Dudman, 49, who held a series of senior jobs with the Sun and was promoted from an assistant editor role to managing editor under Mrs Brooks in 2004. He was made editorial development director for News International last June, and serves as a board member of the Society of Editors.
Chris Pharo, 42, who was promoted by Ms Brooks from news editor to head of news in 2007, is also believed to have been arrested, along with Mike Sullivan, 48, the paper's long-serving crime editor.
Yesterday, police from the Metropolitan Police's Operation Elveden, set up to investigate illegal payments to officers, searched the Sun newsroom in Wapping, London, for evidence after the arrests. The journalists' homes were also searched.
When Mrs Brooks appeared in front of a Commons committee in 2003, she was asked by Chris Bryant MP whether her newspaper had been involved in improper activities. Mrs Brooks replied: "We have paid the police for information in the past."
Andy Coulson, her successor as News of the World editor who later worked as David Cameron's director of communications, rapidly moved to suggest to the committee that any payments were made "within the law".
The News of the World was shut down last July after it was implicated in the phone hacking scandal. Mrs Brooks resigned as News International chief executive the following week. Two days later she was arrested and questioned by police investigating payments to police and the phone hacking scandal, before being bailed.
A News Corporation spokesman said: "News Corporation made a commitment last summer that unacceptable news-gathering practices by individuals in the past would not be repeated.
"It commissioned the Management and Standards Committee (MSC) to undertake a review of all News International titles, regardless of cost, and to proactively co-operate with law enforcement and other authorities if potentially relevant information arose at those titles.
"As a result of that review, which is ongoing, the MSC provided information to the Elveden investigation which led to today's arrests.
"No comment can be made on the nature of that information to avoid prejudicing the investigation and the rights of individuals."
A 29-year-old police officer from the Met's Territorial Policing command was also arrested on suspicion of corruption, misconduct in a public office and conspiracy. He was being questioned at a south London police station.