About 500 protesters gathered at the Chicago Police headquarters and marched peacefully through the city Tuesday night after the release of the video, which depicts Jason Van Dyke, a white 14-year veteran of the police force, drawing his weapon on Laquan McDonald, an African American teen carrying a knife who appears to be crossing a major thoroughfare.
As McDonald veers away from the officers, Van Dyke begins firing, felling McDonald immediately, and then shoots repeatedly at his prone body. A total of 16 shots - all of the ammunition in the officer's clip - were fired.
(Disclaimer: Content in this video could be disturbing for viewers)
"The officer in this case took a young man's life, and he's going to have to account for his actions, and that's what today is all about," said Garry F. McCarthy, the Chicago police superintendent. McCarthy called on city residents to demonstrate peacefully.
"People have a right to be angry," he said. "People have a right to protest; people have a right to free speech. But they do not have a right to commit criminal acts."
The video's release arrives at a time of heightened racial tension nationally, and amid intensified scrutiny of police forces following a series of fatal encounters between law enforcement and black men and boys. It is rare for a police officer to be charged in a fatal shooting, and the first-degree murder charge is the most severe that Van Dyke could have faced.
Earlier in the day, police in Minneapolis said that they had taken three men into custody after gunshots were fired at protesters at a Black Lives Matter rally in that city Monday night, wounding five demonstrators in an attack that inflamed tensions already high over the recent police killing of an unarmed black man.
The unrest, propelled into the public eye after the killing of Michael Brown in Ferguson, Missouri, last year, has included a wave of demonstrations in city streets and debates on college campuses across the country.
The rapid developments Tuesday - an officer charged, a horrific video's release - recalled similar situations that unfolded this year. In North Charleston, S.C., and Cincinnati, similar videos showing officers fatally shooting black men were released publicly, and in both cases officials also announced murder charges the same day.
Protests followed in both cities, but the demonstrations were far less heated than those in cities such as Ferguson and New York after grand juries there declined to indict officers.
Chicago officials appeared before the news media in the late afternoon, acknowledging the likely public outcry over the video and calling on residents to avoid violence in response. In a statement, the McDonald family asked "for calm in Chicago."
"No one understands the anger more than us but if you choose to speak out, we urge you to be peaceful," the statement said. "Don't resort to violence in Laquan's name."
Anita Alvarez, the state's attorney for Cook County, Ill., said in outlining the charges against Van Dyke that the officer's actions "were not a proper use of deadly force."
"He abused his authority, and I don't believe the use of force was necessary," Alvarez said.
She also said, "With these charges, we are bringing a full measure of justice that this demands."
Van Dyke was the only officer to fire at McDonald, who police said used his knife to slash the tires of a squad car when he encountered the officers. Van Dyke was on the scene near McDonald for less than 30 seconds before he began firing, Alvarez said.
Van Dyke's attorney, Daniel Herbert, has said that the officer feared for his life when he opened fire.
"We hold our police officers to high standards, and obviously in this case Jason Van Dyke violated . . . basic moral standards that bind our community together," Chicago Mayor Rahm Emanuel (D) said at a news conference announcing the video's release.
In April, the Chicago City Council approved a $5 million settlement with McDonald's relatives. But some in the community say they are angry that it took Alvarez's office so long to charge Van Dyke.
"There is no way this length of time should have gone on so long when the video showed all this evidence," Michael Pfleger, a Catholic priest in Chicago, said Tuesday. "Shame on them for being so late."
In other places, such as Minneapolis, protesters have been demanding that video footage of fatal police shootings be released.
Protesters have been rallying outside a Minneapolis precinct station since earlier this month when a police officer fatally shot 24-year-old Jamar Clark, an unarmed black man.
The shooting Monday night, which occurred one block from the police station, shook protesters, who nonetheless said they would not be driven away from the demonstration and predicted that more would join as a result.
"I'm out here to make sure those cowards know that they didn't scare anybody," Demetrius Pendleton, 46, who runs a local homeless shelter, said during a march Tuesday afternoon. "We want to see justice, and we won't stop until we get it."
In a Facebook post, Black Lives Matter Minneapolis said that "white supremacists" attacked the group Monday night "in an act of domestic terrorism" and that the group vowed not to be intimidated.
Police said Tuesday that they had three white men in custody: a 23-year-old arrested in Bloomington, a nearby city, as well as a 26-year-old and a 21-year-old who turned themselves in to investigators. A fourth person, a 32-year-old Hispanic man arrested in south Minneapolis, was released after it was determined that he was not at the shooting scene, police said.
Minneapolis police said they received multiple 911 calls Monday night about the gunfire, a block away from the 4th Precinct. All five people, who had been protesting at the police building, suffered injuries that were not considered life-threatening, officials said.
Protesters said that the shooting occurred after a group of people - three men and a woman, all wearing ski masks - were seen filming the activity. The people in ski masks went down Morgan Avenue, and some of the demonstrators followed them.
A fight ensued and then gunshots rang out, said Henry Habu, who has been at the protests since Sunday. Habu said that protesters had been told to watch out for white supremacists wearing masks or camouflage clothing, and he said the group filming the demonstrations matched those descriptions.
After the gunfire at 10:40 p.m. Monday, police said, dozens of officers rushed to the scene and began investigating. Demonstrators rushed to tend to the injured, and others flocked to the area.
"It was very somber," said John Jacobson, who said he had arrived 30 minutes later after seeing a Black Lives Matter post on Facebook. "Like a wake, and you're looking for familiar faces."
One demonstrator was shot in the leg and was among "four boys on the ground," said Carrie Brown. "He just kept saying, 'Don't leave me, don't leave me,' " she said.
Federal authorities said Tuesday that they were in close contact with local police.
"The Department of Justice is aware of the incident and is coordinating with the Minneapolis Police Department to assess the evidence and determine if federal action is appropriate," the department said in a statement.
The Minneapolis rallies were prompted by the Nov. 15 shooting of Jamar Clark. Police have said that Clark was a suspect in an assault and interfered when paramedics tried to treat the assault victim.
"At some point during an altercation that ensued between the officers and the individual, an officer discharged his weapon, striking the individual," the Minnesota Department of Public Safety said in a statement.
The officers involved were Mark Ringgenberg and Dustin Schwarze. Both have served with the Minneapolis police for a little more than a year, and each has been an officer for a total of seven years, according to the Bureau of Criminal Apprehension, the state agency investigating the shooting. Police have not said which officer fired the fatal shot.
The FBI has announced that it will conduct its own investigation into Clark's death. The U.S. attorney's office in Minnesota and Justice Department prosecutors said they will review evidence to see whether there were any federal civil rights violations.
Some witnesses have said that Clark was handcuffed when he was shot. Police have said that did not appear to be the case. Drew Evans, superintendent of the Bureau of Criminal Apprehension, has said that authorities were still working to determine whether Clark was handcuffed when he died.
Demonstrators have called on police to release video footage of the shooting. Evans has said that there is no complete video of the shooting, although investigators have multiple videos that he said related to the encounter.
The actions during the march Tuesday afternoon were essentially identical to those that have played out in dozens of U.S. cities in the year since Brown was killed in Ferguson. The crowd danced to Kendrick Lamar's "Alright," shouted out the names of a number of those killed by police in the past year - Brown, Tamir Rice in Cleveland, Walter Scott in North Charleston - and chanted, "No justice, no peace, prosecute the police."
The Minnesota protesters' demands were nearly identical to those made by demonstrators in Ferguson, Cleveland and Baltimore.
"We want justice," said Jayme Ali, a local minister who marched near the front of the crowd.
Ali, 44, was born and raised in Minneapolis and said it is time for the city to address issues of racial inequity, especially in policing.
Although she was present for many of the protests' first days, she had not come out for three days because of an illness.
But the shooting of the five activists Monday night inspired her back into the street. She wanted to show that she wasn't afraid. As she marched from the police station to City Hall, her hands gripped a homemade cardboard sign with a warning for the nation: "This could be your city next."
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