Angel Valodia Matos of Cuba was banned for life from any event sanctioned by the World Taekwondo Federation after intentionally kicking an Olympic referee in the face and throwing a punch at a judge. Matos had been receiving medical attention for a toe injury, but he failed to get up before the one minute clock elapsed, thus disqualifying him. His response was not very sportsmanlike.
I doubt this YouTube link will last very long, but here it is...
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