After a day of peaceful demonstrations at local malls, protesters appeared at police headquarters in Ferguson, Mo., late Friday, resulting in 15 arrests.
One of those taken into custody was being held on suspicion of assaulting a law enforcement officer, according St. Louis County police, who confirmed the arrests.
"We are going to build an army that will take you on! ... We are building a class movement to destroy you!" shouted one woman over a loudspeaker.
Protesters were arrested after they moved into the street.
The crowd had previously been walking on South Florissant Road holding banners, nearly clashing with police and National Guardsmen on several occasions. Some of the protesters called for a communist revolution.
A large contingent of Ferguson police officers retreated into headquarters shortly before 10 p.m.
Cam McQueen, an activist from Massachusetts, said she was upset to see the New York protesters take over what had been a mostly peaceful day of demonstrations.
"Today had been a beautiful day. We had three peaceful actions in three upscale malls, and we shut them down," she said. "So for something like this to happen tonight, I just hope people understand these are not the people who have been on the ground for 115 days."
About 300 protesters staged protests Friday at the Galleria Mall, West County Center and Chesterfield Mall in and around St. Louis, temporarily closing them on one of the year's biggest shopping days. Many employees and shoppers expressed support for the demonstrations.