Uefa is investigating an allegation of racist chanting towards England players during their Euro 2024 opener on Sunday.
The governing body announced it would conduct a disciplinary investigation into “alleged discriminatory behaviour” following England’s 1-0 victory.
It is not known who made the complaint but it is understood it did not come from the England camp.
Anti-discrimination organisation Fare is known to have had observers at the Arena AufSchalke during the Group C game in Gelsenkirchen, Germany.
Meanwhile, the Serbian Football Association has been charged by Uefa after objects were allegedly thrown during the game.
The charges also include “transmitting a provocative message unfit for a sports event”.
Earlier, the Kosovo Football Federation said it had made a complaint to Uefa about the “display of flags, slogans and chants by Serbian fans”, which it said contained “political and racist messages against Kosovo”.
European football’s governing body said: “The Uefa Control, Ethics and Disciplinary Body (CEDB) will decide on the matter in due course.
“Furthermore, a Uefa Ethics and Disciplinary Inspector will conduct a disciplinary investigation regarding alleged discriminatory behaviour.”
England defeated Serbia with Jude Bellingham’s 13th-minute header.
Police said eight people had been temporarily detained following a brawl between England and Serbia fans before the game, seven from Serbia.