'Stand up to racism' says AC Milan keeper Maignan
Maignan talked of a mob mentality that shrugged off responsibility as a factor that allowed the phenomena to continue in contemporary society.
"It is easy to act in a group, in the anonymity from the stands.
"The spectators who were in the stand, who saw everything, who heard everything, but who chose to remain silent, you are complicit," said the goalkeeper in a post on X, formerly Twitter.
Maignan said that he had first heard monkey chants during Milan's match at Udinese on Saturday when he collected the ball for his first goal kick, after which he "said nothing".
"Then for the second goal kick they did it again. I called to the dugout and the fourth official and I told them what had happened. I said that we can't play in these conditions."
The referee Fabio Maresca stopped play for a period of five minutes.
"The Udinese club, which only spoke of an interruption to the match, as if nothing had happened, you are complicit," he insisted.
"The authorities and the prosecutor, with everything that is happening, if you do nothing, you will also be complicit," he added.
"This isn't the first time this has happened to me. And I'm not the first this has happened to. We've made statements, publicity campaigns, regulations, and nothing has changed."
The Italian Football Federation is due to decide on Tuesday what punishment to hand out to Udinese - from a fine to a stadium ban.
The club announced on Sunday that it would assist the authorities in charge of the investigation "to shed light on what took place and take every measure possible to punish those responsible".
Saturday was not the first time that Maignan has been racially abused by supporters in Italy as he was targeted by a Juventus fan in September 2021.
Racism is so persistent in Italian football that in August it caused the United Nations' Committee on the Elimination of Racial Discrimination to raise a "red flag" over abuse at sporting events.
FIFA president Gianni Infantino called for worldwide stadium bans for fans and "automatic forfeits" for teams whose supporters hurl "abhorrent" abuse following the incidents.
Italy, a country governed by a coalition led by the far-right Brothers of Italy party, is rife with fascist football fan groups, in particular among the hardcore "ultras" who make most of the atmosphere at stadiums.