FIFA said on Monday it had opened disciplinary proceedings against the Serbian football association following the team’s bad-tempered FIFA World Cup clash with Switzerland.
Football’s governing body said it was looking at several potential breaches of its disciplinary code including the misconduct of players and officials, and discrimination.
FIFA referred to “incidents” during the group stage game, without saying what they were.
Fans during Friday’s match in Qatar, which Switzerland won 3-2 to progress, were told to “stop all discriminatory chants and gestures”.
It was not immediately clear what triggered the announcement but it followed a confrontation between Swiss captain Granit Xhaka and Serbia’s players.
The flashpoint in the second half drew in Switzerland forward Breel Embolo and Serbia substitutes ran onto the pitch at Stadium 974 to remonstrate with Swiss players before the referee brought the situation under control.
Xhaka comes from a family with roots in Kosovo, the former Serb province with a majority ethnic Albanian population.
Serbia were already being investigated by FIFA after the team hung a controversial flag in their changing room before they lost to Brazil in Qatar.
The Kosovo football federation filed a complaint with FIFA after photos showed a version of the Serbian flag with a map that depicted Kosovo as part of the country and included the slogan “there will be no surrender”.