Minneapolis authorities launched an investigation into police response during a downtown street protest that turned unruly Wednesday night in which chemical spray used by officers hit a 10-year-old boy.
Police Chief Janeé Harteau and Mayor Betsy Hodges called a news conference Thursday asking witnesses to come forward.
"It is critical for everyone involved that we complete a thorough investigation, so I need the public's help," the chief said. "We must have the full set of facts."
In a police report, authorities said the protesters Wednesday night repeatedly "engaged motorists, jumping on cars and trying to pull open doors. Officers pushed back the crowds to get the motorists out of harm's way. … Chemical aerosol was used to drive back the hostile crowds."
About 100 people closed down two blocks of downtown during the protest, which had as its focus the March shooting death of a black youth, Tony Robinson, by a white police officer in Madison, Wis. On Tuesday, authorities decided the officer would face no charges.
Susan Montgomery, the mother of the boy who was sprayed, said that she and her son, Taye, were among the protesters.
Montgomery, of St. Paul, said the officer had been near her group of fewer than 10 protesters for some time.
At one point, the officer drove up abruptly to Montgomery and the others with his siren on and lights flashing on S. 7th Street. "People started running. It seemed like he was mad at that point," she said.