Mexico has been active in drug production and importation for decades and still produces a significant percentage of the heroin and marijuana consumed in the United States. Mexican traffickers have also been successful in the corruption of many public officials, who provide such services to the traffickers as the protection of goods and intelligence information. The traffickers have also established a working relationship with Colombian traffickers who use Mexico as a transshipment point for Colombian cocaine in transit. South American countries such as Peru and Bolivia participate in global drug trafficking by producing the coca leaf for later use in cocaine manufacturing. Colombia contributes to the drug business by converting coca leaves into cocaine hydrochloride (powder). The Medellin cartel, one of the most powerful organized crime groups in the world, resides in Colombia. Cuban nationals residing in the United States are also involved in drug trafficking, and, although their official numbers are relatively small, they exert influence in many major U.S. cities due to hundreds of associate members. 2 figures.