The Paraguayan drug rackets - mostly carried out through Ciudad del Este (known as Puerto Stroessner back then) - was just one of these (albeit the most profitable).
Paraguay also developed an active and highly problematic auto theft rackets at the time. Under Stroessner Paraguay had no motor vehicle registry at all - which was no coincidence, since it was well known that most of its relatively few cars had in fact been stolen from Argentina or Brazil (my grandmother's Peugeot 404 among them, we later found out).
Of course, neither racket was as heinous as the massive child trafficking ring ran by Stroessner's henchmen. Thousands of (mostly white) children were kidnapped for sale to foreign pedophiles (especially in Germany, Brazil, and the U.S.); many of those kidnapped were, again, Argentine or Brazilian children from towns just across the border, or whose parents had been careless during a visit to Paraguay.
Thank you, Judi, for all your research.