Milan, Italy - Lazio blasted "a psychosis focusing on either a minority or non-existent incidents" after racist and anti-Semitic chants overshadowed the team's 4-1 Italian Cup win over Novara at the Stadio Olimpico on Saturday.
The chanting early in the first half was heard in Lazio's North End and was aimed at the club's bitter city rivals AS Roma, with taunts of "Yellow, red, and Jewish" and "This Roma that looks like Africa."
It also targeted police who had clashed with fans on Wednesday at Piazza della Liberta in the capital when celebrations to mark the club's 119th anniversary turned violent.
Eight police were injured and four supporters arrested.
"I am here to talk about the racist and anti-Semitic chants that are supposed to have happened," club spokesman Arturo Diaconale told a press conference after the game.
"I am one of the 98 percent of people in the stadium who didn't hear them.
"The club naturally condemns any racist or anti-Semitic chants, but we have to consider the dimensions of the phenomenon.
"I think it's a form of psychosis focusing on either a minority or non-existent incidents.
"I read about chants as if the entire stadium had participated. We mustn't turn this into a mass panic over nothing. I invite our colleagues in the media to give the right degree of consideration to incidents that would normally be ignored," added Diaconale.
Italian police are also investigating after AS Roma supporters allegedly distributed anti-Semitic leaflets in the north of the city on Wednesday to coincide with the anniversary of Lazio, with whom they share the Stadio Olimpico.
The leaflets, signed by a group of Roma ultras, read: "Lazio, Napoli, and Israel, same colours, same flags. S**t."
It comes just over a year after Lazio ultras posted anti-Semitic stickers depicting Holocaust victim Anne Frank in a Roma jersey in the Stadio Olimpico.
Italian football is still reeling after violence before Inter Milan's game against Napoli on Dec. 26.
There were violent clashes before the game in the San Siro with an Inter supporter killed after being hit by a car, while Napoli defender Kalidou Koulibaly was subjected to racist chanting on the pitch.
Roma host third-division Virtus Entrella at the Stadio Olimpico on Monday.