Gulf Cartel
Both of the Gulf Cartel leaders ignored the command, and Treviño Morales did not wait to avenge the death of his friend. On 30 January 2010, Treviño Morales kidnapped and murdered 16 Gulf Cartel members in Reynosa, Tamaulipas, marking the start of the cartel war between the Gulf Cartel and Los Zetas in the Mexican states of Tamaulipas, Nuevo León, and Veracruz that has left thousands of people killed. Los Zetas used violent and intimidation tactics to expand, emerging with a notorious reputation as Mexico's most violent drug trafficking organization. Through these tactics, it has managed to take control of most of the territories "owned" by the Gulf Cartel where they had once essentially served as a single organization.