More Violence in Ferguson, Missouri

Demonstrators react to tear gas fired by police during ongoing protests in reaction to the shooting of teenager Michael Brown, in Ferguson, Missouri, August 18, 2014. REUTERS/Lucas Jackson

Angry protestors in Ferguson, Missouri, Aug. 18, 2014, for Michael Brown. Brown's shooting has sparked more than a week of protests, riots and looting.

Demonstrators drag a portable toilet onto the roadway during protests in Ferguson, Missouri August 18, 2014.

Protesters walk through a cloud of tear gas Monday, Aug. 18, 2014, in Ferguson, Missouri. (AP Photo/Jeff Roberson)

A man is detained after a standoff with police Monday, Aug. 18, 2014, during a protest for Michael Brown. (AP Photo/Charlie Riedel)

Police take up positions after being shot at Monday, Aug. 18, 2014, in Ferguson. Police have used riot gear and tear gas and Gov. Jay Nixon ordered the National Guard to help restore order Monday. (AP Photo/Jeff Roberson)

A man is led away after being detained by police. Ferguson, Missouri, Aug. 18, 2014.

Law enforcement personnel meet for a briefing prior to the arrival of National Guard troops in Ferguson, Missouri, August 18, 2014.

National Guard troops arrive at a mall complex that serves as staging area for the police in Ferguson, Missouri, Aug. 18, 2014.

A police officer stands next to graffiti and a burned out Quick Time gas station in Ferguson, Missouri, August 18, 2014.

Missouri State Highway Patrol Captain Ron Johnson (center R) greets rapper Nelly on West Florissant during ongoing protests in reaction to the shooting of teenager Michael Brown in Ferguson, Missouri, Aug. 18, 2014.