A man has been questioned by police investigating alleged computer hacking.
He was detained by Metropolitan Police detectives at his home in Cardiff on suspicion of offences under the Computer Misuse Act and the Regulation of Investigatory Powers Act, Scotland Yard said.
The man, 55, is not directly linked to any news organisation or the activities of journalists.
He was questioned at a police station in the Cardiff area before being bailed to return to a south London police station in October 2012, pending further inquiries, Scotland Yard said.
He is the sixth person to be arrested as part of Operation Tuleta, the probe into alleged computer hacking.
This is linked to the Met's investigation into newspaper phone hacking, Operation Weeting.
So far, 24 people have been arrested as part of the phone-hacking inquiry, and 41 as part of an investigation into alleged corrupt payments to officials, Operation Elveden.