WARSAW - UEFA is to investigate alleged racist chanting during Euro 2012 matches directed towards Italian striker Mario Balotelli and Czech Republic defender Theodor Gebre Selassie.
No disciplinary proceedings have been started at this stage, European football's organising body said.
"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," a UEFA spokesman said.
A Spanish fans' group has said some of its supporters abused Manchester City striker Balotelli. Gebre Selassie was meanwhile reported as saying he "noticed" racist chants directed at him.
No official complaints have been made to UEFA by Italy or Czech Republic.
UEFA is also investigating the throwing of missiles, including fireworks, and a pitch invasion by a spectator during Sunday's game between Croatia and Ireland in Poznan, Poland, which Croatia won 3-1.
UEFA's control and disciplinary body will deal with the case on Friday.
UEFA has already opened disciplinary proceedings against the German, Portuguese and Russian football federations since the tournament began in Poland and Ukraine on Friday.
Germany's DFB has been charged after its team's supporters threw missiles onto the pitch in Lviv, Ukraine in their 1-0 defeat of Portugal. The Portuguese federation FPF faces proceedings for a delayed kick-off to the second half.
UEFA is to deal with the cases on Thursday.
The Russian federation is also facing charges after fans threw fireworks on the field and displayed illicit banners in Friday's 4-1 victory over the Czech Republic in Wroclaw, Poland. The case is set to be dealt with on Wednesday.