Héctor David Delgado Santiago (23 December 1975 – 15 January 2013), commonly referred to by his alias El Metro 4, was a suspected Mexican drug lord and high-ranking leader of the Gulf Cartel, a criminal group based in Tamaulipas. Born and raised in Matamoros, Tamaulipas, El Metro 4 initiated his criminal career by working with Los Metros, an enforcer gang of the Gulf Cartel.