The leaders of several large police departments across the country are decrying the use of force by the officers involved in the arrest of George Floyd, the black man who died after a white police officer pressed his knee into his neck for eight minutes.
Chicago Police Superintendent David O. Brown said that Floyd's death was "caused by the unacceptable actions of a police officer."
"What took place in Minneapolis earlier this week is absolutely reprehensible and tarnishes the badge nationwide, including here in Chicago," Brown said in a statement.
The police commissioners of New York City and Philadelphia also criticized the actions of the officers preceding Floyd's death. The Oakland, California, police chief said the department was "deeply disturbed" by what it saw in video of the arrest.
Full coverage of George Floyd's death and protests around the country
Three San Francisco Bay Area police unions also were among those criticizing the use of force.
Floyd, 46, died Monday after video showed he was pinned to the ground by a white Minneapolis police officer as Floyd was heard saying he couldn't breathe.
Police were responding to a call about a forgery after Floyd was accused of allegedly using a counterfeit $20 bill at a grocery store.
The officer who knelt on Floyd's neck and the three other officers involved in the arrest were fired the next day, and there are investigations into whether charges should be filed, including by the FBI and state authorities.
Floyd's death, and the video of his arrest, has sparked outrage and protests across the country. In Minneapolis, demonstrations turned violent Wednesday and Thursday nights with stores looted and buildings set afire, including a police precinct.
New York City Police Commissioner Dermot Shea said in a statement: "What we saw in Minnesota was deeply disturbing. It was wrong."
"We must come together, condemn these actions and reinforce who we are as members of the NYPD," Shea wrote. "This is not acceptable ANYWHERE."
Philadelphia's police commissioner, Danielle M. Outlaw, said that "throughout the nation, communities of color are tired of reliving atrocities such as this over and over again," and she applauded the swift actions taken by the Minneapolis police chief, Medaria Arradondo, which Outlaw said sent a clear message that such conduct won't be tolerated.
Protests have occurred in some of the cities that have condemned the actions seen in the video.
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Demonstrations occurred in New York City on Thursday, and police said that there had more than 30 arrests, including one person who allegedly punched an officer in the face and another accused of hitting an officer with a garbage can, NBC New York reported.
Protests also occurred in Denver on Thursday, with marchers calling for action, NBC affiliate KUSA reported.
The city's police chief, Paul M. Pazen, said in a statement Thursday that "the actions and type of force used by the Minneapolis police officers in the video are inexcusable and contrary to how we train our officers."
Brown, the Chicago police superintendent, said that the actions that led to Floyd's death made the job of Chicago police — which has been trying to rebuild trust following incidents of its own, including a racially charged killing in 2014 — more difficult.
Brown said that he had also ordered mandatory training for all officers on "positional asphyxiation," when someone is restrained in way that they can't breathe.