Mario Cárdenas Guillén is the brother of the Mexican drug lord who was the former leader of what group?
Osiel Cárdenas Guillén Osiel Cárdenas Guillén (born May 18, 1967) is a former Mexican drug lord and the former leader of the Gulf Cartel (Spanish: "Cártel del Golfo" ) and Los Zetas. Originally a mechanic in Matamoros, Tamaulipas, where he was born, he entered the Gulf Cartel by helping Juan García Abrego, the capo at the time; when García Ábrego was arrested in 1996, some infighting erupted within the cartel. Osiel Cárdenas eventually took control by killing his friend and contender Salvador Gómez, earning Cárdenas the nickname ""El Mata Amigos"" (The Friend-Killer).
King Tone Antonio Fernandez, also known as King Tone, is the former head of the Latin Kings (the largest Hispanic street gang in the US). In 1999, Fernandez was sentenced to 12 to 15 years for conspiring to sell narcotics. He is the main figure in the HBO documentary, "Latin Kings: A Street Gang story", which was released in 2007. He is also featured in the book, "The Misfit Economy," by Alexa Clay, which was published in 2015. Upon his release, Fernandez has shared his insights as a former gang leader and political activist, and how that relates to the "legitimate world".