An Italian study led by Maria Pareschi of the Italian National Institute of Geophysics and Volcanology in Pisa indicates that a volcanic collapse of the eastern flank of Mount Etna 8,500 years ago would likely have caused a 10-storey ( ) tsunami to engulf some Mediterranean coastal cities within hours .
A study by Maria Pareschi of the Italian National Institute of Geophysics and Volcanology in Pisa says that a volcanic collapse of Mount Etna 's Eastern flank which happened 8,500 years ago likely caused a 10-storey ( 40 m or 131 ft ) megatsunami that hit and engulfed some of the Mediterranean coastal cities within hours .