 It was the only publication in Cuba that unmasked the judicial farce in the USA regarding the murder of Chicago martyrs, an incident that originated on the traditional celebration of May Day.However, the impossibility of worker journals to race with the self-called “great press” or “serious press” (which belonged to American partnerships, bourgeois and Cuban politicians) in the first two decades of past century anarchistic groups edited Tierra y Bandera Social, the Liga of Trabajadores Cubanos (Cuban Workers League) had in Alerta, their official newspaper; La Voz Obrera became in spokesman of the Partido Socialista de Cuba (Socialist Cuban Party), y Lucha de Clases, in 1924, with biweekly edition and directed by Carlos Baliño, was the first Cuban Marxism-Leninism newspaper.Years later there was Juventud Obrera (1929), that reach five years of life, so others like El Trabajador y Bandera Roja, both belonging to Communist Party.