Counterintelligence

Offensive measures using enemy information

Counterintelligence (counter-intelligence) and its primary subfield, counterespionage (counter-espionage), are activities aimed at protecting an agency's intelligence program from an opposition's intelligence service. It includes gathering information and conducting activities to prevent espionage, sabotage, assassinations or other intelligence activities conducted by, for, or on behalf of foreign powers, organizations or persons. Many countries will have multiple organizations focusing on a different aspect of counterintelligence, such as domestic, international, and counter-terrorism.

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