Many Italians fought a guerrilla war in the "Africa Orientale Italiana", after the surrender at Gondar of the last regular Italian forces in november 1941.
They fought in the hope of an Italian victory with the help of Rommel in Egypt and in the Mediterranean (called in 1942 by Mussolini "the Italian Mare Nostrum"), that would originate a possible return of the Axis in Eastern Africa.
She became an active member of the Fronte di Resistenza (Front of Resistance), an Italian organization which fought the Allies in the Italian guerrilla war in Ethiopia from December 1941 until the summer of 1943.( in Italian).
In August 1942 she managed to enter inside the main ammunition depot of the British Army in Addis Abeba and blow it up, somehow surviving the huge explosion. This act of sabotage destroyed the ammunition for the new British sten machine gun and delayed the deployment of this "state of the art" weapon for many months. Doctor Dainelli, even if less known than lieutenant Amedeo Guillet (), was famous as one of the few Italian woman who participated actively in the Italian guerrilla operations against the British troops after the East African Campaign (World War II).
She was nominated, after the end of the war, for the Italian iron medal of honor ("croce di ferro").