The investigation, which began in June 2025 following a report of a missing minor, concluded in April with the arrest of one person and the investigation of 14 others. The individuals allegedly used falsified documents to process fraudulent residency registrations.

The inquiry started when officers visited the address where the minor was registered and residents denied knowing him. After locating the mother and handing over the child to a different address than the one officially recorded, an investigation into the property's registration status was opened.

Subsequent checks revealed an unusually high number of people registered at the same address in the Carabanchel district. This uncovered an alleged system using fictitious rental contracts and falsified registration forms with allegedly untrue data and signatures to register migrant individuals.

Authorities suggest that the registrations were carried out without the knowledge or consent of the legitimate owner of the property used for the procedures.