De la Rosa and Pizana created small bands, somewhat like military companies, constructed of 25 to 100 men.[1] The Rio Grande Valley was the focus of the raids where trains were fired upon and telegraph wires and poles were cut down. On August 8, nearly 60 raiders struck the Norias Ranch, leaving five men dead when chased by American forces.[2] U.S. authorities learned from this raid and from the wounded left behind that support from the Mexican Carranza government supplied the raiders, half of the men being Mexican citizens.