Singer Charlotte Church told ITV News the amount of information held on her by some national newspapers during her teens was "all encompassing of everybody I'd ever known".
She told us she first became aware of Operation Motorman in 2004 when Alec Owens, who led the investigation for the Information Commissioner's Office, showed her a "huge, huge book with a phenomenal amount of data" in.
She added: "It was literally about everybody I'd ever known, anybody I'd ever come in contact with. That's what really took us by surprise about it. Just like lots of my parents' friends and some of my mum's old work colleagues."
But the 26-year-old said the discovery made "a lot more sense to how they (some of the press) were getting their stories" about her.
Seperately Church and her parents recently settled phone hacking claims with News of the World for a total of £600,000. Her lawyer told the High Court that the now-defunct newspaper targeted her and her voicemail messages repeatedly, and unlawfully obtained her private medical information and details of her personal relationships with her family and friends.
Following the settlement Church vowed to focus her energies on assisting the criminal investigation and the Leveson Inquiry, and intended to dedicate her portion of the settlement to protecting herself and her children from further invasions of privacy.