Serie A could be suspended after an Inter Milan supporter died following a fight with Napoli fans in which four people were stabbed.
The 35-year-old Inter fan is believed to have been rushed to hospital after being hit by a van which, according to reports in Italy, was being driven by Napoli fans an hour before kick-off at the San Siro on Wednesday.
He underwent emergency surgery but died from his injuries.
It was also reported in the Italian press that rival fans had been armed with chains and hammers and around 60 people were involved in the brawl.
Italian FA president Gabriele Gravina has threatened to stop league games from taking place following the tragic incident.
Inter won 1-0 with Napoli having two players sent off, including Kalidou Koulibaly. The Senegal international defender was subjected to racial abuse with the away side asking for the match to be halted after the 27-year-old was repeatedly subjected to monkey noises.
Gravina said the racist chants and violence outside the stadium were “no longer tolerable”.
“Football is the heritage of true supporters and as such should be defended from all those who use it as a tool to create tension,” he said.
“We condemn all forms of both physical and verbal violence, with the aggravating circumstance of racial discrimination. We do not tolerate such behaviour ruining football.”
The Mayor of Milan, Giuseppe Sala, made a public apology on Thursday, describing the racist chanting as a ‘shameful act’ and asking Koulibaly’s forgiveness.
“The boos aimed at Koulibaly were shameful,” said Sala on Facebook. “A shameful act towards a true athlete who wears the colour of his skin with pride.”
The mayor, who was at the San Siro for the match, said he would continue to go to games but would not tolerate any racist chanting.
“I will continue to watch Inter but at the first chant I will make a small gesture. I will get up and leave. I will do it for myself, aware that whoever abuses a black athlete won’t give a damn about me,” said Sala.
“I apologise to Kalidou Koulibaly on my own behalf and on behalf of the people of Milan who testify to feeling that we are brothers even in these difficult times.”
Napoli boss Carlo Ancelotti revealed that the staff had asked the referee three times to suspend the match because of the chants.
“The solution exists,” Ancelotti told Sky. “You have to stop the match. You just have to know when, after how many announcements. And if we don’t know, then next time we may have to stop play ourselves.”
Koulibaly apologised on Twitter for the defeat and being sent off but said, “I am proud of the colour of my skin, to be French, Senegalese, Neapolitan: a man.”
Meanwhile, Inter will play two home league games behind closed doors following the racist abuse of Koulibaly.
The Italian side will also play a third match at the San Siro without opening the ‘curva’ section of the ground, popular with the ultras.
Inter’s next three home league games are against Sassuolo on January 19, Bologna on February 3 and Sampdoria on February 17.