Ismael Zambada Garcia, alias "El Mayo," heads a faction of the Sinaloa Cartel. He has used his connections in the Mexican government to push his influence steadily north toward the U.S. border and south toward Cancun, leaving a trail of imprisoned and dead colleagues in his wake.

Along with his now imprisoned partner Joaquin Guzman Loera, alias "El Chapo," El Mayo is one of the most storied traffickers in Mexico. Originally a farmer from Sinaloa, he has made and broken many alliances with other organizations. His partnership with Guzman has been cited as a big reason why the Sinaloa Cartel is the strongest in the hemisphere. He originally worked with the Juarez Cartel in the 1980s and 1990s.

After the death of head of the Juarez Cartel Amado Carrillo Fuentes, alias "El Señor de los Cielos," El Mayo created his own organization. With the slow demise of the Tijuana Cartel, he has sought to expand his routes through Sonora and Baja California. He also controls much of the heroin production and shipment from Mexico into the United States.

In recent years, El Mayo has suffered the loss of several key members of his inner circle. Authorities have arrested his brother, two sons and a nephew. One of his sons, Ismael Zambada, alias "El Mayito," was extradited to the U.S. in 2010. In 2012, El Mayo's alleged right-hand man, Manuel Torres Felix, alias "El M-1" or "El Ondeado", was killed in a shootout with the military.

Some analysts surmised that El Mayo might be easing into the shadows, or even retiring, after he appeared on the front cover of the Mexican investigative news magazine Proceso in 2010. However, several years on he remains at large and is believed to still be active.