Uefa has confirmed it will investigate reports of racist chanting aimed at Mario Balotelli during Italy's 1-1 draw with Spain in Gdansk on Sunday.
Several news outlets alleged on Monday up to 300 Spanish fans made monkey chants at the Manchester City striker during the game, in what is the latest incident of racist abuse at the tournament.
And a Spanish fans' group has said some of its supporters did abuse the 23-year-old, despite Madrid-based newspaper AS accusing the Daily Mirror of "inventing" racism.
The Uefa statement added: "Following the provision of new independent information today, regarding the two cases of alleged racist chanting in the Spain-Italy and Russia-Czech Republic matches, Uefa is now conducting further investigations."
Already the Dutch squad and the Czech Republic's Theodor Gebre Selassie have suffered racial chanting in the opening three days of the tournament.
Uefa, who have long been criticised for a frivolous stance on racism, attempted to suggest the incident during Holland's open training session on Thursday last week was not racially-motivated.
Had it not been for Oranje captain Mark van Bommel's insistence, it is unlikely they would have acknowledged the chanting was not just an "isolated" incident, but sickeningly audible.
Balotelli, 23, vowed before the tournament he would walk off the field of play and even "kill" someone if they threw a banana at him.