One of the fans is in serious condition after a day riddled with fan trouble involving Dutch supporters in Milan.
Sportmediaset indicate the stabbings may have committed by Milan ultras but those reports are not confirmed at this time.
The trouble began early on Wednesday when Ajax fans attacked a protest by the Forconi as they were upset at having been stuck in traffic due to the manifestation.
Corriere dello Sport reports that the stabbings may have been a result of payback for the incidents earlier in the day.
They are reports of further incidents involving drunk fans throwing objects in the city at Milan Point and and in front of Hospital Fatebenefratelli.
More details will no doubt be released in the coming hours as the situation develops.
Follow Adriano Boin on Twitter: @Boin44