General strike of the Argentinе working class — Semаna trágica ensued between January 9 and 16 — was for many years the major battle between workers on the one hand and a capitalists and the state on the other. It started as a strike in metallurgical factory “Vasena” and turned into a general strike on January 9. The immediate reason for the protest was the police killed four workers and injured 40. The strike received support from anarchist FORA-V and syndicalist FORA-IX. However, it was anarchist’s workers who played the main role in it. The strike bellowed into violent confrontation between laborers and the police. Nevertheless, the violence and mass mobilization convince the upper and middle classes that the radical government, president H. Yrigoyen lost control and that Bolshevik revolution is just around the corner. Acting on this perception armed groups of civilians took matter into on their own hands. Together with the police they attacked working-class neighborhoods, destroying labor offices, beating, shooting and arresting workers. The white terror continued from the tenth to the fourteenth of January. The army entered the city and repressed the general strike. The Tragic Week ended but many of the ruling classes continued to fear a revolutionary outbreak caused by communist penetration. The Semana Trágica has become one of the main signs of the nationalist movement. Nationalists believed that Russian agents, agents of the Soviet lead provoked the general strike. They portrayed the Semana Trágica as a war fought by the nation against foreign enemy — communism. The general strike led the formation in early 1919 of an organized paramilitary movement, the League Patriotic Argentina which during postwar years enjoyed strong support among the upper and middle classes, the military, church and the leading business association. The Semana Trágica also marked the first political intervention of the army.