Final answer:
IMSI catchers are electronic devices used for mobile phone surveillance, operated by law enforcement agencies and intelligence organizations.
Step-by-step explanation:
IMSI catchers are electronic devices used for mobile phone surveillance. They are typically operated by law enforcement agencies and intelligence organizations.
IMSI stands for International Mobile Subscriber Identity, which is a unique identifier assigned to each mobile phone. IMSI catchers work by impersonating legitimate cell towers, tricking mobile phones into connecting to them, and allowing the operator to intercept the phone's communication.
Examples of organizations known to operate IMSI catchers include government agencies such as the police, intelligence agencies, and military units.