Carlos Castaño Gil (May 16, 1965 – April 16, 2004) was the founder of the Peasant Self-Defenders of Córdoba and Urabá (ACCU), a far-right paramilitary organization in Colombia. Castaño founded the group with his siblings following the death of their father by the FARC with an emphasis on counter-insurgent warfare. The group would later become the more notorious United Self-Defense Forces of Colombia, or AUC. The successor group was accused of numerous atrocities against suspected rebels and the civilian populace, the most notable of these being the Mapiripan Massacre of 1997 where at least 30 civilians were slaughtered, some of whom were dismembered alive. The AUC also maintained ties with drug trafficking organizations such as cartels. Castaño's reign of terror came to an end on April 16, 2004, when he was murdered at the hands of his own men for attempting to break ties with the lucrative drug trade.
