Virginia Wheeler is the 23rd arrest under Operation Elveden, which is investigating suspected payments to police officers and public officials.
The operation is not about seeking journalists to reveal confidential sources in relation to information that has been obtained legitimately, the police said.
The police did not name Wheeler in its announcement, but she has been identified by The Guardian and the BBC.
The police said that she had been arrested "by appointment on suspicion of corruption under the Prevention of Corruption Act 1906 and aiding and abetting misconduct in a public office (contrary to common law) and conspiracy in relation to both offences".
Wheeler, 32, who was in custody at a south London police station, was reportedly arrested on the basis of information provided to police by News Corporation's Management Standards Committee.