Hundreds gathered to remember the police shooting of the unarmed black teen, who was killed during an altercation with Officer Darren Wilson.
The incident sparked months of protests in the city and throughout the country, with critics calling the slaying an act of racial prejudice. Wilson has maintained that he acted in self-defense, and he was not indicted in the shooting.
A St. Louis County grand jury and the U.S. Justice Department found insufficient evidence to prosecute Wilson, who resigned from the police department in November. However, the Justice Department released a report in March that found racial bias in the Ferguson Police Department and municipal courts; the report caused several city officials to resign.
The shooting on Sunday occurred after two groups started firing at each other on West Florissant Avenue, which has served as the centers for protests in Ferguson, The New York Times reports.
AP Photo / Jeff Roberson
Belmar said the man opened fire on officers as they drove toward him. Police returned fire from the vehicle and then chased him on foot. The man fired at them again and all four officers ended up shooting him.
"They were criminals; they weren't protesters," Belmar said of the two groups firing on each other. "Protesters are the people out there talking about a way to effect change."
He added: "We can't afford to have this kind of violence, not only on a night like this but any point in time, if we're going to move forward in the right direction."
Protests on Sunday were otherwise largely peaceful, police said, with five arrests, according to the Associated Press.
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