BERKELEY, Calif. (AP) — Local media reports say a demonstration last night in Berkeley, California, against police killings of unarmed black men in Missouri and New York began peacefully, until splinter groups broke off.

Police say some of the demonstrators began throwing rocks, bottles, pipes and smoke grenades at officers and vandalized several businesses. Police responded by lobbing tear gas. Officials say several officers were struck, but there were just two reports of injuries.

At least six people were arrested.

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