 The Ludlow Massacre in Colorado and police dispersal of the Tarrytown protests enraged most radicals.In June, members of the Lettish Anarchist Red Cross, including Berg, Hanson, Berger, and IWW member Arthur Caron began plotting a bomb attack to assassinate Rockefeller.Berg, Hanson, and Caron began to collect dynamite from various sources, storing it in Louise Berger's apartment on New York's Lexington Avenue.