 The "Saber noise" (ruido de sables) incident of September 1924, provoked by discontent of young officers, mostly lieutenants from middle and working classes, lead to the establishment of the September Junta led by General Luis Altamirano and the exile of Alessandri.However, fears of a conservative restoration in progressive sectors of the army led to another coup in January, which ended with the establishment of the January Junta as interim government while waiting for Alessandri's return.The latter group was led by two colonels, Carlos Ibáñez del Campo and Marmaduke Grove.