Protesters have overturned barricades and swarmed the steps of the St Louis federal court in a second day of protests over a decision not to indict a white police officer over the killing of an unarmed black 18-year-old.
About 300 people marched from a park to the court and remained there for about 30 minutes before heading elsewhere. They chanted: "You didn't indict. We shall fight."
It was one of several protests in the St Louis area today over yesterday's grand jury decision not to indict officer Darren Wilson for killing Michael Brown on August 9.
The decision means Wilson will not face any state criminal charges in the shooting, which reignited debates over relations between police and minority communities, even in cities far from the suburb of Ferguson.
In Ferguson, smoke billowed from burned-out businesses and glass littered the pavements in front of shops whose display windows were smashed during protests.
The destruction appeared to be much worse than protests that erupted after Brown's death, with more than a dozen businesses badly damaged or destroyed. Authorities reported hearing hundreds of gunshots, which for a time prevented fire crews from fighting the flames.
The violence erupted despite pleas for calm from the Brown family and President Barack Obama, who tried to strike a middle ground as he addressed the tensions.
America's first black president said the case demonstrates how a legacy of racial discrimination has fed distrust between law enforcement and minorities, but he also sought to dispel the notion that race relations have deteriorated.
Ferguson mayor James Knowles criticised what he said was the delayed deployment of the National Guard as the protests broke out. Earlier in the day, Missouri governor Jay Nixon ordered additional members from the military reserve force to the suburb.
Wilson's lawyers issued a statement praising the grand jury's decision and saying the officer, who has remained out of the public eye since the shooting, is grateful to his supporters.
"Law enforcement personnel must frequently make split-second and difficult decisions," the lawyers said. "Officer Wilson followed his training and followed the law."
There were 61 arrests in Ferguson overnight, many for burglary and trespassing, St Louis County Police spokesman Brian Schellman said. There were 21 arrests in St Louis, the city's Mayor Francis Slay said.
At least 18 people were injured, including one person who is recovering from a gunshot wound.
Thousands of people rallied - mostly peacefully - in other US cities on Monday night.
The Justice Department is conducting a separate investigation into possible civil rights violations that could result in federal charges, but investigators would need to satisfy a rigorous standard of proof in order to mount a prosecution.
The department has also has launched a broad probe into the Ferguson Police Department, looking for patterns of discrimination.
Prosecuting attorney Bob McCulloch said witnesses had given the grand jury inconsistent accounts of the shooting, including whether Brown's hands were raised and whether he was stumbling or charging towards Wilson.
Speaking for nearly 45 minutes, McCulloch never mentioned that Brown was unarmed when he was killed.
Brown's family released a statement saying they were "profoundly disappointed" but asked that the public "channel your frustration in ways that will make a positive change".
Authorities released more than 1,000 pages of grand jury documents, including Wilson's testimony.
He told jurors that he initially encountered Brown and a friend walking in a road and, when he told them to move to a pavement, Brown responded with an expletive.
Wilson then noticed that Brown had a handful of cigars "and that's when it clicked for me", he said, referring to a radio report minutes earlier of a robbery at a nearby convenience store.
Wilson said he asked a dispatcher to send additional police and then backed his vehicle up in front of Brown and his friend. As he tried to open the door, Wilson said Brown slammed it back shut.
The officer said he pushed Brown with the door and Brown hit him in the face. Wilson told grand jurors he was thinking: "What do I do not to get beaten inside my car?"
"I drew my gun," Wilson told the grand jury. "I said, 'Get back or I'm going to shoot you.'
"He immediately grabs my gun and says, 'You are too much of a pussy to shoot me'," Wilson told grand jurors. He said Brown grabbed the gun with his right hand, twisted it and "digs it into my hip".
Asked why he felt the need to pull his gun, Wilson told grand jurors he was concerned another punch to his face could "knock me out or worse".
After shots were fired in the vehicle, Brown fled and Wilson gave chase. At some point, Brown turned around to face the officer.
Wilson has recorded an hour-long interview with journalist George Stephanopoulos from ABC News
ABC will feature the interview on Nightline and its evening and morning news programmes. It s aid it will also make the full interview available on its website ABCNews.com.