MINNEAPOLIS (WCCO) — Minneapolis Police Chief Janeé Harteau said she has launched an investigation after allegations that police went too far, even potentially harming a young boy, while monitoring a rally outside city hall Wednesday evening.

Wednesday night’s rally was organized by the group Black Liberation Project, in what was supposed to be a peaceful protest. It is still unclear when exactly things changed, but when they did it was all over social media.

The group was protesting the shooting death of a 19-year-old Tony Robinson of Madison, Wisconsin. The biracial teenager was shot by a white police officer back in March. Authorities said Robinson was on drugs at the time and was acting erratically before he was shot.

Earlier this week, prosecutors announced that officer would not be charged in his death. About 100 people were at the rally.

One protester posted a video of a police officer spraying chemicals towards the crowd. But what is really creating outrage is a picture posted on Twitter of a young boy who appears to have been sprayed with chemicals.

A mother who said her son was taking part in the protest with her claims the 10-year-old was sprayed with a chemical by police. She said milk was used to try to ease the burning in his eyes.

Another video was posted to Twitter showing others doing the same. They allege police also sprayed them with chemicals.

At a press conference Thursday morning, Harteau said she has opened a full investigation and is gathering surveillance video in order to figure out what happened, as well as interviewing witnesses.

“We need to speak with the people who marched. We need to know what their experiences looked like. We also need to hear from motorists who were fearful, from people who had property damage as well,” Harteau said. “We need to see any and all video from all angles in the case. We must have a full set of facts.”

Mayor Betsy Hodges also spoke at the press conference.

“We do have an incident before us that we are investigating, and that we do take very seriously,” she said.

On Wednesday night, she tweeted that she is listening to the community’s concerns and that she is “asking the right questions.”

Nekima Levy-Pounds, president of the NAACP in Minneapolis, said accountability is the first thing her group seeks in response to the incident.

“Beyond that, we would like to see a review of the policies and practices that allow the indiscriminate use of pepper spray, to be used at a peaceful demonstration,” she said.

Harteau said she reached out to the mother of the 10-year-old boy, and she said they had a good conversation.

The office of Police Conduct Review, which is made up of citizens and officers, will investigate the incident.

The Minneapolis Police Federation is asking people to help with the investigation and not pass judgment until it is complete.

Federation President-Elect Bob Krull said he believes when all is said and done, the officers’ actions will be justified.

He said there was damage to property and to the American flag at the protest. He added that officers did what they had to do to protect people and property.

The Black Liberation Project released a statement on Facebook stating that MPD took violent action against a protest of predominantly black youth, a departure from previously “peaceful” support from MPD officers at other marches and rallies.

Another video uploaded to Vimeo following Wednesday’s demonstrations shows a group of protesters in front of the police station on 4th Street South. Two people are shown burning the American flag while officers stood nearby. The group was shown chanting: “If we don’t get no justice, they don’t get no peace.”

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The Black Liberation Project and Black Lives Matter are organizing another rally at 7 p.m. Thursday at the Hennepin County Government Center.

They said Thursday’s event is meant to support the 10-year-old boy along with victims of police abuse around the country.