Three Ajax supporters reportedly suffered stab wounds during an incident that occurred before the Dutch side's Champions League goalless draw with AC Milan.
It has been claimed that Ajax and Milan fans got involved in violent altercations throughout the day, while those protesting against Enrico Letta's government also clashed with the crowds.
According to the Daily Mail, a police spokesman has revealed that one fan has been left seriously injured after getting stabbed in the stomach, while two others were wounded in the buttock and leg.
The authorities believe that none of the injuries are life threatening.