Lazio’s 1-0 victory was overshadowed by the racist abuse of AC Milan midfielder Tiemoue Bakayoko.
Lazio fans could be heard chanting “this banana is for Bakayoko” before and after the match at Milan’s San Siro stadium, according to Italian news agency ANSA and video footage circulated on social media.
Italian publication, Gazzetta dello Sport, also reported that inflatable bananas were spotted in the stadium.
A group of Lazio ultra fans displayed a long banner reading “Honour to Benito Mussolini”, and sang fascist songs and performed the Nazi salute near the city’s Piazza Loreto, where the fascist dictator’s body was strung up in 1945, the Gazzetta dello Sport also reported.
Authorities reportedly identified 22 people responsible for the Mussolini banner.
The fans are expected to be charged for “fascist manifestation”.
In Italy “apology for fascism” is a crime, but some cases have been thrown out in recent years on freedom of speech grounds.
In a statement after the game, Lazio attempted to distance itself from the racist abuse but also attacked the media for “considering [all] Lazio supporters responsible”.
“SS Lazio clearly distance ourselves from behaviour and demonstrations that do not in any way correspond to the values of sport that this club has promoted and supported for 119 years,” the statement read.
“Lazio also reject and contest the simplistic tendency of the media to consider the entire Lazio fanbase responsible for the actions of a few isolated elements, for motivation that has nothing to do with passion for sport.
“The club has always fought for the respect of law and fairness in behaviour.”
Italian football has struggled to prevent racist abuse this season.
Earlier this month, Juventus young gun Moise Kean was racially abused in a game in Cagliari, with his teammate Leonardo Bonucci widely condemned for then saying it was partly the striker’s fault.
Italy’s national team coach Roberto Mancini was among those to call on authorities to clamp down on racism.
Mayor of Milan, Giuseppe Sala, insisted the northern Italian city “is and will remain forever a profoundly anti-fascist city”.
Meanwhile, Italy’s deputy prime minister Matteo Salvini condemned the incident.
“No tolerance for any form of violence, physical or verbal. I thank the police who are following the incident carefully. Football must be an occasion of celebration and communion, not for fighting or confrontation,” he said on Twitter.
