Demonstrators protesting the killing of an unarmed black man during a scuffle with police joined Minneapolis officials Thursday in urging protesters to remain calm after a night of violence.
Demonstrators have been camping for days outside 4th Precinct police headquarters in Minneapolis, where officers used pepper spray to disperse crowds who hurled bottles, rocks and bricks Wednesday night. They are protesting the killing of Jamar Clark, 24, who died of a gunshot wound to the head Sunday.
Police told NBC News on Thursday that no arrests were made. But one officer was treated for reaction to a chemical irritant sprayed by a segment of protesters, and 12 squad cars were damaged, Police Chief Janee Harteau told reporters Thursday.
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After the clash ended, three explosive devices that police described as "Molotov cocktails" were thrown at officers, Harteau said. The suspects, whom authorities described as political anarchists based on a flag they were carrying, remained at large Thursday, police said.
Harteau and Minneapolis Mayor Betsy Hodges both praised the majority of demonstrators for protesting peacefully, blaming the violence on outside elements.
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Citing Minneapolis' history as a center of large-scale peaceful public activism, Hodges said she was determined to ensure the rights of protesters. At the same time, she said, she was responsible for protecting her police department and public spaces.
"We cannot allow violent conduct to endanger anyone" — including the protesters — she said.
Ezra Hyland, who has helped organize Black Lives Matter demonstrations after Sunday's shooting, joined Harteau and Hodges to call for calm.
Hyland, an African-American literacy specialist at the University of Minnesota, also blamed outside elements for the violence, calling them "agents-provocateurs."
"I hope and pray there will be justice for Jamar, but at the same time I pray for peace" for the community, he said.
Other protest leaders joined Hyland in calling for calm.
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The protesters, led by the local chapter of the NAACP, are demanding that authorities release video of the shooting Sunday in north Minneapolis that was recorded by several sources. State investigators have said they won't release the video while the investigation is continuing.
Police say Clark was a suspect in an assault and was interfering with paramedics who were trying to treat the victim. An autopsy found that he died of a gunshot wound to the head.
It remained unclear whether Clark was handcuffed during the scuffle. The state Bureau of Criminal Apprehension said it is looking into whether he was restrained.
The officers involved — Mark Ringgenberg and Dustin Schwarze — have been with the department for 13 months, and both have been police officers for seven years.
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The officers' races haven't been made public, but the FBI is conducting a civil rights investigation.
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Minneapolis NAACP President Nekima Levy-Pounds, meanwhile, called for peaceful demonstrations.
"We are asking the community to exercise restraint in the midst of grief, hurting and unanswered questions, and we demand the same respect from the Minneapolis Police Department," she said at a rally Thursday.
Meanwhile, Lt. Bob Kroll, director of the Minneapolis police union, said protesters shouldn't have been allowed to gather at the precinct headquarters in the first place.
"That is not a place to exercise your First Amendment rights," Kroll told reporters Thursday. "That is police property."
Kroll said the officers involved in the shooting told state investigators that Clark was non-compliant with verbal commands and that at one point he got hold of one of the officers' gun belt and gun.
He said the officers' would be exonerated, and he criticized city officials who he said hadn't stood by their police.
"Someone needs to stand up in a leadership position and make a positive statement about the officers," Kroll said.