Department of State, SECRET, "Conversation with Argentine Intelligence Source," April 7, 1980. In this revealing memorandum to Ambassador Castro, James J. Blystone, the Regional Security Officer (RSO) at the US Embassy in Buenos Aires, details his April 2 meeting with an Argentine intelligence source. The anonymous Argentine source describes how Horacio Campiglia and Susana Binstock, two militant Montoneros, were captured by Argentine officers of Battalion 601 (in coordination with Brazilian intelligence), taken to Argentina and held at the Campo de Mayo Army base. Campiglia and Binstock who were never seen again, are amongst the more than a hundred victims included in the Operation Condor trial.

Department of State, SECRET, "Conversation with Argentine Intelligence Source," April 7, 1980.
In this revealing memorandum to Ambassador Castro, James J. Blystone, the Regional Security Officer (RSO) at the US Embassy in Buenos Aires, details his April 2 meeting with an Argentine intelligence source. The anonymous Argentine source describes how Horacio Campiglia and Susana Binstock, two militant Montoneros, were captured by Argentine officers of Battalion 601 (in coordination with Brazilian intelligence), taken to Argentina and held at the Campo de Mayo Army base. Campiglia and Binstock who were never seen again, are amongst the more than a hundred victims included in the Operation Condor trial.
 http://www.gwu.edu/~nsarchiv/NSAEBB/NSAEBB416/docs/800407dos.pdf