A woman arrested on Monday by detectives investigating allegations of voicemail hacking has been bailed until July.
Scotland Yard said the 42-year-old suspect was detained on suspicion of money-laundering offences.
She was held after attending a south west London police station by appointment at around 11am and questioned by officers from Operation Weeting, Scotland Yard's phone-hacking investigation.
The Met said in a statement: "She was arrested after attending a south-west London police station by appointment at approximately 11:00hrs on suspicion of money laundering offences, contrary to Section 327 of the Proceeds of Crime Act 2002 and is currently being questioned."
The development comes after a 37-year-old journalist was arrested on Friday as part of the Operation Elveden inquiry.
She was later released on bail pending further inquiries. A total of 30 people have been arrested since last July as part of Elveden,
Police launched Operation Weeting, the inquiry devoted specifically to phone hacking, after receiving "significant new information" from News International on January 26 last year.
Operation Elveden was launched months later after officers were given documents suggesting News International journalists made illegal payments to police officers.
Officers also launched three related operations: the Sasha inquiry into allegations of perverting the course of justice; Kilo, an inquiry into police leaks; and Tuleta, the investigation into computer-related offences, as the inquiry escalated.
Metropolitan Police figures showed there were 829 potential victims of phone hacking, of whom 231 were said to be uncontactable.
The scandal has already led to the closure of the News of the World after 168 years, prompted a major public inquiry, and forced the resignation of Met Commissioner Sir Paul Stephenson and his assistant John Yates.
Former News International chief executive Rebekah Brooks, her husband Charlie and four others were charged earlier this month with perverting the course of justice in relation to the phone-hacking probe - the first charges since the investigation began in January last year.
UPDATED: 20:50 28 May 20112 Bail details added