Counter-espionage
From Wikipedia, the free encyclopedia.

Espionage operations intended to identify enemy spies. Most countries have government agencies whose purpose includes counter-espionage. Examples include the Federal Bureau of Investigation in the United States, MI5 in the United Kingdom, and Défense et Sécurité du Territoire in France.

The original article can be found at: http://en.wikipedia.org/wiki/Counter-espionage.
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