Hours before a set curfew was to begin officer in riot gear moved in to clear the streets after police say protesters began lobbing Molotov cocktails.
Police used smoke canisters and tear gas to try and gain control of what they describe as a "very dangerous situation".
"We had shots being fired on officers, Molotov cocktails, and the looting and vandalism," said Captain Ron Johnson of the Missouri State Highway Patrol.
Early reports indicate two to three people in the crowd were injured by gunfire, with none of those shootings apparently involving police, and at least four businesses were damaged and looted.
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