A serving police officer and two Sun journalists, including one from south-east London, have been arrested by detectives investigating alleged corrupt payments to public officials.
The 39-year-old Wiltshire officer was arrested at his home in the county at 6am, Scotland Yard said, on suspicion of misconduct in a public office and conspiracy to commit misconduct in a public office.
A 51-year-old journalist was detained at his home in Bristol and a 32-year-old journalist was held at his house in south-east London, both on suspicion of conspiracy to corrupt and conspiracy to cause misconduct in a public office.
News International confirmed that both men work for the Sun newspaper, but did not give any more details.
A Metropolitan Police spokesman said: "Today's arrests are the result of information provided to police by News Corporation's management standards committee.
"They relate to suspected payments to a public official and suspected disclosure of confidential information by a police officer and are not about seeking journalists to reveal confidential sources in relation to information that has been obtained legitimately."
The arrests bring the number of people arrested in Operation Elveden, the investigation into alleged corrupt payments to public officials, to 50.