Police in riot gear move in on people staging a protest for Michael Brown, who was killed by a police officerAug. 9 in Ferguson, Mo. The Associated Press

People run from tear gas as police disperse a crowd staging a protest for Michael Brown on Sunday. The Associated Press

In this photo taken with a fisheye lens, people leave a McDonald's restaurant after taking refuge from tear gas in Ferguson, Mo., Sunday. The Associated Press

A man tries to recover after being hit by tear gas in Ferguson, Mo., Sunday night. The Associated Press

Missouri State Highway Patrol Capt. Ron Johnson speaks Sunday during a rally at Greater Grace Church for Michael Brown, who was killed by police Aug. 9 in Ferguson, Mo. The Associated Press

The Rev. Al Sharpton, in background, raises his hands with the crowd during a service Sunday for the Michael Brown family at a church in Ferguson, Mo. A police officer fatally shot Brown, an unarmed black teenager, on Aug. 9.