Real Madrid s Brazilian forward Vinicius Junior confronts Valencia s officials as he leaves after being sent off the pitch by the referee during the Spanish league football match between Valencia CF and Real Madrid CF at the Mestalla stadium in Valencia on May 21, 2023. AFP
The arrests come amid an international outcry after racist abuse was hurled at the 22-year-old Brazilian international during a Spanish league match on Sunday.
The four men, who were arrested in Madrid, are "suspected of a hate crime for hanging from a bridge a mannequin with Vinicius' shirt," police said in a statement.
Three of the men are members of an ultra fan group of a Madrid football club who had been identified during matches as representing a high risk of violence.
While the authorities did not name the club the ultras belonged to, Spanish media said they were part of Atletico's ultras.
Police accompanied their statement with images of the suspects in handcuffs and escorted by officers.
The dummy wearing Vinicius Junior's jersey was hung by the neck from a highway bridge near Real Madrid's training ground on January 26 ahead of the club's match against Atletico Madrid.
A banner in the red and white colours of Atletico bearing the message "Madrid hates Real" was also draped over the bridge.
The message is often used by one of Atletico Madrid’s ultra fans groups, although it denied at the time being responsible for the display.
Vinicius Junior has often been targeted by opposition fans in La Liga and was once more in a 1-0 loss at Valencia on Sunday.
The game was held up for several minutes and the referee wrote in his post-match report that shouts of "monkey" had been directed at Vinicius.
Spanish prosecutors opened an investigation into the incident, which was condemned by Brazilian President Luiz Inacio Lula da Silva and Spanish Prime Minister Pedro Sanchez.
Real Madrid had filed a complaint "in order that the facts be investigated and those responsible be held accountable".
The club said the chants, in its view, "constitute a hate crime".
There is growing anger in Brazil, where the lights of the Christ the Redeemer statue in Rio de Janeiro were turned off for one hour in solidarity with the player.
"Black and imposing," Vinicius tweeted of the darkened statue, saying he was moved and thanked followers for their support.
"But I want, above all, to inspire and bring more light to our fight," he added.
The Brazilian government has formally protested to the Spanish ambassador and will lodge an official complaint with authorities in Madrid.
Brazil "deeply regrets that no effective measures have yet been taken to prevent the recurrence of these racist acts," the government said in a statement.
After Sunday's match, the player posted a video montage on Instagram of many of the incidents he has experienced while in Spain, calling them "inhuman".
In a strongly-worded statement, he also said that "today, in Brazil, Spain is known as a country of racists".
"The league that once belonged to Ronaldinho, Ronaldo, Cristiano (Ronaldo) and Messi now belongs to racists," Vinicius added.
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