Human Intelligence (HUMINT) is intelligence gathered by means of interpersonal contact, a category of intelligence derived from information collected and provided by human sources.
(NATO Glossary of Terms)
Human Intelligence (HUMINT) is the collection of information from human sources. The collection may be done openly, as when FBI agents interview witnesses or suspects, or it may be done through clandestine or covert means (espionage). Within the United States, HUMINT collection is the FBI’s responsibility. Beyond U.S. borders, HUMINT is generally collected by the CIA, but also by other U.S. components abroad. Although HUMINT is an important collection discipline for the FBI, we also collect intelligence through other methods, including SIGINT, MASINT, and OSINT.
https://www.fbi.gov/about/leadership-and-structure/intelligence-branch
Collection includes clandestine acquisition of photography, documents, and other material; overt collection by personnel in diplomatic and consular posts; debriefing of foreign nationals and US citizens who travel abroad; and official contacts with foreign governments.
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