 The Sinaloa Cartel began to contest the Gulf Cartel's domination of the coveted southwest Texas corridor following the arrest of Gulf Cartel leader Osiel Cárdenas in March 2003.The "Federation" was the result of a 2006 accord between several groups located in the Pacific state of Sinaloa.The cartel was led by Joaquín "El Chapo" Guzmán, who was Mexico's most-wanted drug trafficker with an estimated net worth of U.S. $1 billion.