Detectives investigating alleged hacking of stolen mobile phones and corrupt payments to public officials have made two arrests.
A prison officer was held at his home in Northampton on suspicion of conspiracy to corrupt and misconduct in a public office.
He is the 44th person to be arrested as part of Operation Elveden, the investigation into alleged bribes.
The arrest was a result of information passed to police by News Corporation's management standards committee, Scotland Yard said.
Another man, aged 28, was arrested under Operation Tuleta, which is looking at computer hacking, the alleged illegal accessing of stolen mobile phones and other privacy breaches.
He attended a south London police station by appointment and was arrested on suspicion of offences under the Theft Act, then bailed until December 9.
Operations Elveden and Tuleta are being run alongside Operation Weeting, the inquiry into phone hacking.
So far 25 people have been arrested under Weeting and eight people charged, and 13 detained under Tuleta.
A Prison Service spokeswoman said she could not comment on individual cases.
She said: "The Prison Service is committed to dealing robustly with all forms of corruption, including the unauthorised disclosure of sensitive information for financial gain. Such activity is a fundamental breach of the Civil Service Code and may constitute the criminal offence of misconduct in public office."