Arrostito was born in Buenos Aires, the daughter of a middle-class couple, and grew up in a leftist background, ideologically opposed to Peronism.
[1] Norma Arrostito left the communist party in 1967, and joined the organization Comando Camilo Torres, where she met Mario Eduardo Firmenich, Carlos Ramus and Fernando Abal Medina.
[6] The organization carried out in a series of operations against the security forces, which ended on 1 June 1970 in the kidnapping and murder of General Pedro Eugenio Aramburu, a former de facto President and one of the leaders of the Revolución Libertadora which overthrew Perón in 1955.
[8] On 20 September, a police raid caught Ramus and Abal Medina in a restaurant in William Morris, a neighborhood in the western outskirts of Buenos Aires, killing both of them after a brief shootout.
[10] After the military departed from power, Arrostito and her camarades of Montoneros were granted an amnesty by a decree of Héctor José Cámpora, who had won the presidential elections of March 1973.
[11] On 3 September 1973, the magazine La Causa Peronista published an interview with Arrostito and Firmenich where they described in detail the kidnapping and assassination of Aramburu.
In his May Day speech, Perón took sides and denounced Montoneros as imberbes ("beardless brats") and mercenaries to the service of foreign interests.