[1][2] The group named themselves after Efraín Plaza Olmedo, a Chilean anarchist responsible for a shooting that on July 14, 1912, fired at a crowd in the heart of Santiago, killing 2 young men from the wealthy class.

[10][11] In the early morning of November 3, 2009, an improvised explosive detonated in front of the Hotel Marriott Santiago de Chile, in the Las Condes district, causing material damage and a slightly injured guard.

[12][13][14][15] The group claimed responsibility for the attack, justifying its disagreement with neoliberalism and social inequality in Chile and calling the owners of the hotel chain "defenders and administrators of this order of hunger and slavery.

[20][21][22] On January 15, 2010, an explosive device detonated inside a Falabella store located in the Plaza de Armas, leaving material damage and three people slightly injured (including a minor).

[23][24][25] A month later the group released a statement criticizing the attack, mentioning that it was rendered "unclear and unintelligible" since they claim that it affected civilians and that they were not the main target of the libertarian movement, pointing more to "centers of power" and government buildings.