Batallón de Inteligencia 601

The Batallón de Inteligencia 601 (Spanish for "601st Intelligence Battalion") was a special military intelligence service of the Argentine Army whose structure was set up in the late 1970s, active in the Dirty War and Operation Condor, and disbanded in 2000. Its personnel infiltrated and collected information on guerrilla groups and human rights organisations; and coordinated killings, kidnappings and other abuses.

Source: Wikipedia — Batallón de Inteligencia 601 (CC BY-SA 4.0)