There have been calls for calm in the US, following Friday's court verdict that cleared a US teenager of murder.
Kyle Rittenhouse, 18, had argued he was acting in self-defence when he shot dead two men and injured a third during racial unrest last year.
The not-guilty verdict has deeply divided the country.
Calls for calm have come from officials and also families of the victims, whose lawyers said what is needed now is "justice, not more violence".
A riot was declared by police in the city of Portland, Oregon on Friday evening, as some 200 people started breaking windows and threatening to burn down the local Justice Center.
There were also protests in Chicago and New York, but they were relatively low-key compared to the widespread civil unrest that the US has seen previously.
Rittenhouse said he was acting in self-defence when he fatally shot Joseph Rosenbaum, 36, and Anthony Huber, 26, and injured Gaige Grosskreutz, 28, in August 2020 in the city of Kenosha, Wisconsin. He has been cleared of all charges.
The teenager and the men he shot are all white. However, the incident happened during violent protests over the shooting of a black man, Jacob Blake, by a white police officer.
Jacob Blake's uncle was outside the court when the verdict was handed down.
"We're going to continue to fight and we're going to continue to be peaceful. Let freedom ring," Justin Blake said. BBC
Lawyers representing Rosenbaum's estate and Grosskreutz asked for "peace from everyone hurting", adding in a statement that "what we need right now is justice, not more violence".
Huber's family said the verdict "sends the unacceptable message that armed civilians can show up in any town, incite violence, and then use the danger they have created to justify shooting people in the street."
Rittenhouse is now in an undisclosed location, a spokesman for the his family told CBS.
"In this whole situation there are no winners, there are two people who lost their lives and that's not lost on us at all," they said. BBC