 The earthquake is thought to have involved rupturing of the Galatro, Cittanova and Sant'Eufemia faults, which form the southeastern boundary to the Gioia Basin.This magnitude 6.2 event occurred during the night following the first event and struck the area just to the southwest.Most of the damage and casualties appear to have been caused by a tsunami that was set off by a major collapse of Monte Pací into the sea near Scilla shortly after the earthquake.