A group of more than 50 juveniles created a chaotic scene between Loring Park and the Nicollet Mall in Minneapolis Sunday night.
"They were just basically out of control," Minneapolis Police Department spokesman John Elder said.
Participants moved and ran together, slapping one another, damaging a bit of property and generally "acting the fool," he said.
No one was seriously hurt, and a minimal number of arrests were made, Elder said. But the ruckus, which began about 6:30 p.m., took about an hour to clear, and required not only the intervention of First Precinct officers, but also park and transit police, he said.
Elder said he was unclear of the motives of those involved. Asked about the possibility of a "flash mob," he noted that police did not detect the use of social media to spur the gathering.
He added that none of the assaultive behavior appeared to be directed at people outside the group, nor was there any evidence of a bias crime.
Loring Park had been the scene of the annual Twin Cities Pride Festival on Saturday and Sunday.
"These certainly were not the Pride attendees," Elder said.