I believe that your assumption was correct, although I'm not certain exactly what kind of Russian helicopters you're talking about.
However, let me tell you that Russian helicopters are not an uncommon sight in Latin America. They are very prominent, especially in Central America and some South American countries. The reason is that they are very good workhorses and are very cheap to obtain. I actually had the opportunity to ride on a Peruvian Air Force - Russian made helicopter over the Andes a few years ago. I noticed that most of the aircraft that the Peruvian Air Force operates (including fighter jets) are Russian made.
Pan Am - The World's Most Experienced Airline.