Mayor Jacob Frey said the people who are coming to Minneapolis to protest are not residents and are "coming in largely from outside the city."
"Our Minneapolis residents are scared and rightfully so. We've seen longterm institutional businesses overridden. We've seen community institutions set on fire. And I want to be very, very clear. The people that are doing this are not Minneapolis residents," he said at a news briefing on Saturday.
He said the protests earlier this week that were mostly peaceful and were largely attended by those who lived in the city, but "the dynamic has changed."
"Gradually that shift was made and we saw more and more people coming from outside of the city. We saw more and more people looking to cause violence in our communities, and I have to say, it is not acceptable," Frey said.
"This is no longer about verbal expression. This is about violence and we need to make sure that it stops," he added.
St. Paul Mayor Melvin Carter said everyone who was arrested in his city last night was from outside the state.
"What we are seeing right now is a group of people who are not from here," he said.
There were roughly 20 arrests made in St. Paul last night, mostly for burglary, and roughly the same number of arrests in Minneapolis for curfew violations and destruction of property, said John Harrington, commissioner of the Minnesota Department of Public Safety.