UEFA is investigating an incident of alleged racist abuse during England‘s 1-0 win over Serbia in Gelsenkirchen, a source has told ESPN.

The complaint has not come from the Football Association — and therefore any of the England players — which said they did not have any further details on the situation when contacted by ESPN.

UEFA said in a statement on Monday that the Football Association of Serbia was facing charges relating to objects being thrown and the transmission of a provocative message deemed unfit for a sporting event before adding that “an UEFA Ethics and Disciplinary Inspector will conduct a disciplinary investigation regarding alleged discriminatory behaviour.”

The source confirmed to ESPN that this referred to a racist incident which is believed to have been identified by a spotter inside the ground.

England won their Group C opener 1-0 courtesy of Jude Bellingham‘s 13th-minute header, while the fan in question is not thought to have been ejected from the ground during the game.

England face Denmark in Frankfurt on Thursday, the same day that Serbia play Slovenia.