The Seguro Obrero massacre (Spanish: Matanza del Seguro Obrero, lit. 'Workers Insurance's Massacre') occurred on September 5, 1938, and was the Chilean government's response to an attempted coup d'état by the National Socialist Movement of Chile (MNSCh), whose members were known at the time as Nacistas ("Nazis"), with some differences that justified their option for a different name. After a failed coup involving a stand-off and a shootout, about 60 Nacistas who had surrendered after being given assurances, were summarily shot. About twenty others were killed during the fighting.