Sponsored by the National Police Agency, KAIST, Onpoom, Mobigen, S2W, and SKT are collaborating on a research project titled Tracking and identifying devices and call traffic in voice phishing ecosystem. The project aims to develop a comprehensive defense (Defense in Depth) system to address the fundamental issues related to voice phishing. This system includes: Physical localization system for voice phishing devices is a solution for tracking and seizing illegal devices used in voice phishing. By identifying and utilizing LTE signals of illegal devices, their exact location is determined. In addition, mobility and efficiency are guaranteed by developing both vehicle-mounted and portable systems. Police agents can employ this system to trace and seize illegal devices utilized in criminal activities.