Founded in 1963 in the north-western Mexican state of Chihuahua,[1] the People's Guerrilla Group formed in the context of the period preceding the Dirty War.
Left-wing and peasant unrest was near-constant in many parts of the country during this time, in opposition to the Institutional Revolutionary Party government.
The group's primary leader was Arturo Gámiz García, with Pablo Gómez Ramírez as a prominent theoretician and Salomón Gaytán as a military commander.
However, only one of them went into action, as the second had chosen to withdraw as it was unable to find its way, and the third – carrying the heavier weapons – was delayed by impassable roads and swollen rivers caused by torrential rain the previous night.
Among the guerrillas, eight of thirteen were killed: the teacher and GPG leader himself, Arturo Gámiz García, the physician and Escuela Normal Rural "Ricardo Flores Magón" de Saucillo Chih professor Pablo Gómez Ramírez, the student (and Arturo's brother) Emilio Gámiz García, the peasants Antonio Scobell and Salomón Gaytán, the student Oscar Sandoval Salinas, and the teachers Miguel Quiñones Pedroz and Rafael Martínez Valdivia.