A law enforcement officer in a tactical vehicle watches after a device was fired to disperse a crowd on Sunday, August 17, 2014, during a protest for Michael Brown, who was killed by a police officer last Saturday in Ferguson, Missouri. As night fell Sunday in Ferguson, another peaceful protest quickly deteriorated after marchers pushed toward one end of a street. Police attempted to push them back by firing tear gas and shouting over a bullhorn that the protest was no longer peaceful. #

Smoke trails tear gas canisters fired into the air after protests in reaction to the shooting of Michael Brown turned violent near Ferguson, Missouri on August 17, 2014. #

An FBI agent walks past a memorial erected where teenager Michael Brown was shot as the FBI interviewed residents of the neighborhood in Ferguson, Missouri, on August 16, 2014. #

Michael Brown Sr., the father of slain teenager Michael Brown, attends a rally at Greater Grace Church on August 17, 2014. His son was shot and killed by a Ferguson police officer on August 9, 2014. Despite the Brown family's continued call for peaceful demonstrations, violent protests have erupted nearly every night in Ferguson since his death. #

A woman dances during church services at the Greater St Mark Family Church as the community discusses reactions to the shooting of teenager Michael Brown in Ferguson, on August 17, 2014. #

From left, Imani Harris, Cathryn Fraction, Zoi Williams (with hand at her face, bottom), Destiny Barnett and Zion Jamerison pose for a portrait with their signs during a protest of Michael Brown's murder on August 17, 2014 in Ferguson, Missouri. #

A woman looks into the camera during a demonstration to protest the shooting of Michael Brown and the resulting police response to protests in Ferguson on August 15, 2014. #

A protester kicks a tear gas canister back towards police after protests turned violent on August 17, 2014. Shots were fired and police shouted through bullhorns for protesters to disperse, witnesses said, as chaos erupted Sunday night in Ferguson, Missouri, which has been racked by protests since an unarmed black teenager was shot by police last week. #

Demonstrators protesting the killing of teenager Michael Brown by a Ferguson police officer try to stand their ground despite being overcome by tear gas on August 17, 2014. #

Missouri State Highway Patrol Captain Ron Johnson holds a photo of Michael Brown while being interviewed during a peaceful demonstration, as communities react to Brown's shooting on August 14, 2014. #

Demonstrators raise their arms and chant, "Hands up, Don't Shoot", as police clear them from the street as they protest the shooting death of Michael Brown on August 17, 2014. #