The White House says President Barack Obama is being briefed on the situation in a St. Louis suburb where police used tear gas and smoke bombs to repel protesters.
The demonstrations in Ferguson, Missouri, have been sparked by the death of an unarmed teenager who was shot by a police officer. The officer is white and 18-year-old Michael Brown was black.
Obama was expected to speak about the situation Thursday from Martha's Vineyard, the Massachusetts island where he is vacationing. His remarks were expected to follow his second briefing on the matter in as many days.