The Galleanist group was known for their ruthlessness in choosing targets , had avidly participated in successful bomb attacks as far west as Milwaukee and Chicago , and in 1919 had unleashed a campaign of mail bombings to victims all over the country , including two booby-trap bombs sent to District Attorney Fickert and his assistant Edward A. Cunha in San Francisco , the men who had prosecuted Mooney and Billings . Luigi Galleani himself wrote that police had not arrested " the right criminal " , later telling investigators that he was " positively sure " with " mathematical certitude " that Mooney was not the bomber
mail bombings
1919 United States anarchist bombings
Preparedness Day Bombing