After a few incidents reported over the weekend, UEFA has asked Polish and Ukrainian cities to send police to help prevent any further racist abuse at European Championship team training.
The governing body has asked for offenders to be prosecuted, following an accusation that monkey chants were targeted at Netherlands players during a session opened to the public in Krakow, Poland.
UEFA said Monday it wrote to host city mayors to take "all effective and necessary measures including an increased police presence.''
"A letter was also sent to the sports minister of Poland, Joanna Mucha, to ask for the full support of the Polish authorities in dealing with these important matters,'' UEFA said in a statement.
Anyone "engaging in racist behavior be immediately ejected from the stadium and its vicinity, and that criminal proceedings be launched against such individuals'' the statement added.
UEFA describes the Krakow case as "an isolated incident,'' but adds it was "totally incompatible'' with its zero-tolerance policy toward discrimination.
"UEFA is nevertheless confident that the local authorities will adequately deal with the issue,'' the European football body said.
On Saturday, the Czech Republic player Theodor Gebre Selassie was fully aware he was being racially abused by Russia fans at his team's opening game on Friday. "I noticed that," he said. "It was nothing extreme. I've experienced much worse."