"It's time to leave," the officers said. Reporters on the scene said the area calmed down shortly after as action moved elsewhere.

Some people were caught in the crowds, though, and couldn't easily leave. J.R. Grace came for the vigil but never made it because of the blockade. He was disheartened by the events playing out.

"The businesses didn't kill that man. That's not going to solve anything," he said. "That's only going to make things worse."

Gunshots were reported in the area late Sunday, and a SWAT team was seen in the area. Hundreds of police officers from surrounding communities reported on the scene.

"We have officers from just about every department around here," said St. Louis Police Capt. Ed Kuntz. "Obviously we don't want to use force. We are hoping that just the presence is enough."

By 1 a.m. today, he said pockets of stores had been looted from north of Interstate 270 to the city's northern border. Kuntz, who has worked in policing for 34 years, said of the level of looting: "This is the first time I can remember this ever happening here."