Police officials said they would try to find the fans responsible. Mogi Mirim president Rivaldo, a former star midfielder for Brazil, said the club was already looking at the stadium's security cameras to try to find out what happened.
"I'm against these kinds of attitudes from people who are not respectful to each other," Rivaldo said on Twitter. "We are all equal."
He said he was against any punishment to the club, however, because "we can't control the fans' mouths."
On Wednesday, referee Marcio Chagas da Silva said some fans called him "monkey" and told him to "return to the jungle" before a match in the Rio Grande do Sul state championship. He said his car was vandalized and bananas were left on top of it.
"Unfortunately, this type of attitude is still happening in this country," Silva said.
Last month, Brazilian President Dilma Rousseff gave her support to a black Brazilian player who was taunted with monkey chants every time he touched the ball during a Copa Libertadores match in Peru. On her Twitter feed, Rousseff called the incident involving Cruzeiro player Tinga "sad," adding that "sports can never serve as a stage for prejudice."
Racist behavior is a longstanding problem at matches in Europe. FIFA has sponsored anti-racism campaigns that have had modest levels of success, and it has promised to raise more awareness during this year's World Cup.
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