Real Madrid and the Spanish league on Sunday condemned racist insults against Lamine Yamal during Saturday's "clasico," and Madrid said it was working to identify those who abused the Barcelona forward.
Madrid said it "has opened an investigation in order to locate and identify the perpetrators of these deplorable and despicable insults so that the appropriate disciplinary and judicial measures can be taken."
The league said it was going to formally denounce the "intolerable racist" insults and gestures against Barcelona players at the Santiago Bernabeu Stadium.
The league said it "strongly condemns these events" and "remains firm in its commitment to eradicate any type of racist behaviour and hatred inside and outside stadiums. There is no place for this scourge in sport."
The reaction came after videos on social media showed the alleged insults against Yamal after he scored Barcelona's third goal in its 4-0 rout of Madrid. The 17-year-old celebrated in a corner in front of Madrid fans and made some gestures apparently provoking the fans.
A few fans could be heard yelling insults at Yamal and the other Barcelona players.
"Real Madrid strongly condemns any kind of behaviour involving racism, xenophobia or violence in football and sport, and deeply regrets the insults that a few fans uttered last night in one of the corners of the stadium," the club said in a statement.
Madrid has been denouncing racist insults against its forward Vinícius Júnior, who is also Black, for several years, including when he played a match at Barcelona's Camp Nou Stadium.
Four Atletico Madrid fans who allegedly led a social media campaign aimed at promoting racist acts against Vinícius were detained earlier this month.
Barcelona's victory left the Catalan club six points ahead of Madrid at the top of the league standings after 11 matches.