According to Dutch Police, they are investigating a web developer that coded backdoors into sites he worked on with the objective of harvesting customer data.
The report says that records of 20,000 people were discovered.
"It is suspected that he was able to capture usernames and passwords by installing a special script." Rogue Developer Coded Backdoor in Sites to Harvest Customer Data [bbc.co.uk]
The police are contacting the people involved, however, in a twist, scammers have realised this and are also e-mailing people as if from the police, except with with an attachment payload.