What was the most despicable or repulsive political act or display during a particular Olympiad or other international sporting event?

One of the most despicable political acts during an Olympic event occurred at the 1972 Munich Olympics, when a Palestinian terrorist group called Black September took 11 Israeli athletes hostage and eventually killed them. This horrific act not only shocked the world but also highlighted the intersection of politics and sports, as the Games were meant to promote peace and unity. The tragedy overshadowed the athletic achievements of the event and led to heightened security measures in future Olympiads.