Video footage showed a white police officer kneeling on the neck of Floyd, 46, for nearly nine minutes before he died on May 25, triggering outrage and protests across the United States.
"We do urgently need change, we demand change and most importantly, we deserve change. Make it happen, now. Enough is enough," Henry, who manages Major League Soccer side Montreal Impact, wrote on Twitter.
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"Why is this still happening in 2020? Why do the same racists applaud any ethnic minority who plays for the team they support but abuse the same minorities on the street?"
Henry joins other sports figures in speaking out against racism and police violence in the wake of Floyd's death, including basketball great Michael Jordan and Formula One champion Lewis Hamilton among others.
"Why are all the methods we are using to eradicate this from our society not working? It's gone on for too long and we have come too far for this to be tolerated in modern society," the Frenchman added.
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