Dutch squad members Robin van Persie Nigel de Jong: photo - PAP/Jacek Bednarczyk
Around 25,000 packed the Miejski Stadium, the home to the Wisla Krakow club – which was one of the subjects of the controversial BBC Panorama documentary Stadiums of Hate – where the Dutch squad were training.
As the squad jogged over to one side of the stadium, as part of their warm up, the Dutch newspaper Da Telegraaf reports that a “handful” of people – the UK tabloid the Sun calls them “a mob” - jeered and made monkey noises, presumably aimed at black players, including Nigel de Jong and Gregory van der Wiel.
UEFA officials, however, told the AFP news agency that the jeering was in response to Krakow not being chosen as one of the Polish cities – Warsaw, Wroclaw, Poznan and Gdansk – to host Euro 2012 matches.
Dutch captain, Mark van Bommel, who toured the WW II German Nazi Auschwitz death camp site on Wednesday with the Dutch squad, responded angrily to the UEFA denial. “They should open their ears,” he said.
"It is a real disgrace, especially after getting back from Auschwitz that you are confronted with this. We will take it up with UEFA and if it happens at a match we will talk to the referee and ask him to take us off the field," Mark van Bommel said.
Thenews.pl's Krakow correspondent Nick Hodge, who was at the training session but on the other side of the stadium, says that he did not hear any monkey noises coming from that particular section of the crowd.
There were reported chants of “Ole, ole, screw the Euro,” as the Dutch players went passed, however.
Our reporter adds that for a 15 minute period during the training session the atmosphere from that part of the crowd was “menacing and aggressive”.
There was also one member of the crowd with a banner reading “F**k the Euro” - something that has also been seen at an Irish training session.
Nick also says that he heard the usual foul-mouthed chanting by Wisla Krakow fans directed at their arch-local rivals Cracovia.
Clearly sensitive to accusations made in the BBC documentary of racism at Polish football club grounds, Prime Minister Donald Tusk travelled on the newly opened A2 motorway from Warsaw to Lodz, a two-hour drive from the capital, to meet with Poland's first ever black MP, the Nigerian-born John Godson.
After eating a meal of traditional African dishes, Tusk told any football fans hesitating to come to Poland for the tournament: “I warmly invite English people. You will not encounter anything unpleasant here.”
The England national squad will be holding an open training session in Krakow on Friday, and officials will not be wanting another embarrassing incident.
While not mentioning a race problem in Poland, Britain's Foreign Office offers the following advice to those travelling in Ukraine.
“Although the vast majority of visitors experience no difficulties, foreign nationals have been the victims of violent crime in Kyiv and other major cities. In some cases attacks have been racially motivated. Travellers of Asian or Afro-Caribbean descent and individuals belonging to religious minorities should take extra care.” (pg)
UPDATE – UEFA have now admitted that there were “isolated incidents” of racist chanting at the training session, Thursday, but they have not taken any action because they have “yet to receive an official complaint from the Dutch FA”.