Attorney General Eric Holder is in Missouri to assess the crisis in Ferguson.
Holder has meetings scheduled with Ferguson community leaders and elected officials.
He will also talk with FBI and Justice Department officials who are investigating the death of Michael Brown.
The unarmed black teenager was shot and killed by a white police officer more than a week ago. Brown was shot several times.
The incident has prompted several nights of violent protests and clashes with police.
Attorney General Eric Holder is promising a thorough investigation into the fatal police shooting of a black 18-year-old.
Holder is calling for "an end to the acts of violence in the streets."
He says Ferguson's citizens should "join with law enforcement in condemning the actions of looters, vandals and others seeking to inflame tensions."
The Associated Press contributed to this report.