The Senegal international has urged the authorities to identify those responsible and lock them out of the stadiums
Napoli defender Kalidou Koulibaly has alleged a section of Fiorentina fans called him "f*cking monkey" in Sunday's Serie A match staged at Artemio Franchi in Firenze in which his team won 2-1.
The hosts scored first after 28 minutes when Dusan Vlahovic set Lucas Martinez Quarta for the opener.
The visitors then levelled matters in the 39th minute after Lorenzo Insigne's penalty was saved but the rebound fell to Hirving Lozano who found the back of the net.