Bayern Munich chief executive Karl-Heinz Rummenigge said on Thursday he was furious after a youth academy coach's alleged racist remarks led to a police investigation.
On Tuesday, regional television channel WDR published the private messages sent by the unnamed individual, with authorities starting the probe as the Bundesliga champions had received four complaints letters from parents since 2018.
"This issue does not fit with our values, the values that FC Bayern Munich represent," Rummenigge said.
"This case makes me angry because I want to make it clear and one should not forget that Bayern is a club that always has been against racism."
Rummenigge said the outfit's internal investigation into the incident is almost finished and promised "consequences".
The Bavarian's first team wore shirts in support of the Black Lives Matter movement after the death of George Floyd in the USA in May.
The side was founded by Jews in 1900 but their bosses were banned under the Nazi regime in 1933 and their results declined during the Second World War.
The Bayern Munich Campus, where their academy is based, opened in 2017 and is home to the German giants' U9 to U19 teams, as well as where the women's and girls' teams train and play.