UEFA say they are "very concerned" by Inter's apparent failure to follow the European governing body's protocol on racist chants.
Fans at the San Siro hurled monkey chants at Napoli defender Kalidou Koulibaly during Wednesday's match, according to Carlo Ancelotti.
Three announcements were made over the loudspeaker imploring fans to stop the chants, but they continued unabated.
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According to UEFA's protocol, the match should have been suspended at that point but instead the game was allowed to continue.
The Napoli bossAncelotti pointed to that policy in an angry press conference following the match.