NEW YORK (CBSNewYork/AP) —  As an act of violence once again focuses the nation on relations between law enforcement and minorities, the Rev. Al Sharpton said Wednesday that his civil rights organization will stand with the family of the black South Carolina man fatally shot by a white police officer.

Sharpton addressed the killing of Walter Scott at the beginning of his National Action Network conference in New York. Before the South Carolina shooting, the annual gathering had already scheduled a panel discussion on police brutality featuring the families of several black men and boys killed by police in the last year, including Michael Brown in Ferguson, Missouri; Eric Garner on Staten Island; and Tamir Rice in Cleveland.

“We are saying for the sake of this family in Charleston, that not only are we with you, we are saying that there must be national legislation around cameras and police accountability,” Sharpton said.

North Charleston Patrolman Michael Thomas Slager was charged Tuesday with murder after video emerged that shows the officer shooting at Scott as he flees following a traffic stop for a broken tail light. Scott falls after the eighth shot. Slager has said he fired in self-defense.

The video shows the cop dropping an item near the body that could be the Taser, CBS2’s Marcia Kramer reported.

“I thought that my brother was gunned down like an animal,” said Anthony Scott. “It was just unbelievable to me to see that.”

Sharpton said he first heard about the shooting from the director of the National Action Network chapter there, 1010 WINS’ Juliet Papa reported.

“Not until the video came out yesterday did anyone believe Brother (James) Johnson and the family,” Sharpton said.

But Sharpton praised the police and mayor of North Charleston “for doing the right thing” in charging the officer. He called for national reform on police conduct and said he planned to travel to Charleston in the coming days.

Sharpton said he plans to visit the Scott family.

The civil rights leader was flanked by several elected officials, including New York City Mayor Bill de Blasio, who nodded along with Sharpton’s call for reform.

New York was rattled by its own fatal encounter between a black man and a white officer last year. Garner was selling loose cigarettes when he was confronted by police and placed in a chokehold. A witness was recording with a cellphone camera, and the video showed Garner yelling “I can’t breathe” as he toppled to the sidewalk and died.

Though he did not mention Garner by name, de Blasio alluded to his death last summer on Staten Island as he discussed Scott’s death Saturday in South Carolina.

“Once again, we are watching a video. It’s a video that is so disturbing and so painful,” the mayor said. “You can’t watch that as a human being and not feel pain. It makes no sense according to what our core notions of humanity and decency and justice are.

“We all watch movies and TV and we see images of people being shot, but you know it’s fantasy,” de Blasio said Wednesday, WCBS 880’s Rich Lamb reported. “This was the real thing, and it was very, very painful. We find out, of course, as we always do, he was a human being with a family. He’s a Coast Guard veteran. That just make it all the more painful.”

A grand jury did not bring charges against the NYPD officer. Garner’s widow broke down in tears while addressing the conference crowd at a Manhattan hotel.

Asked about how the version of the event changed after the video was released, de Blasio said: “I think it’s cautionary. I think this is part of why we’re very hopeful about what the body camera pilot program will mean” in New York.

Sharpton praised the police and mayor of North Charleston “for doing the right thing” in charging the officer.

The grand jury’s decision led to days of protests that swept through city streets. A gunman cited Garner’s death on social media before he gunned down two NYPD officers in December, which led the city’s police unions into an open revolt against de Blasio, who they blamed for permitting an anti-NYPD sentiment to take hold in the city. The tension between de Blasio and the police has lessened since then.

North Charleston Mayor Keith Summey said Wednesday that Slager been fired.

Summey made the announcement during a news conference that was frequently interrupted by demonstrators chanting “no justice, no peace.”

Police Chief Eddie Driggers said he was “sickened” watching video that was taken by an unidentified witness.

Summey did not answer many questions about what happened before the shooting, saying that was part of state law enforcement’s investigation. He did say that there is dash-cam video of the traffic stop before the shooting, but he has not seen it and it has not been released to the public.

Summey said the officer’s wife is eight months pregnant and the city will cover her insurance until after the baby is born.

The mayor added that to prevent future incidents the city is buying more than 250 body cameras for police.

“Every officer that’s on the street in uniform will have a body camera,” Summey said.

Meanwhile, authorities in South Carolina have released the radio dispatch related to the shooting.

On the recording, Slager can be heard telling a dispatcher that he is conducting a traffic stop on a gray Mercedes-Benz. Breathing heavily, Slager then says he is in a foot pursuit, giving the description: “Black male, green shirt, blue pants.”

The tape appears to have been edited by officials prior to its public release, making it unclear how much time passed between the calls. The dispatcher can be heard calling for all other police units in the area to respond. Several officers can be heard saying they are on the way. In the background, a voice yells “Lie on the ground!”

Seconds later, Slager says: “Shots fired. Subject is down. He grabbed my Taser.”

A voice asks if everyone at the scene is “10-4,’ a radio code often used by officers to mean “OK.”

Slager responds: “Everyone is 10-4, except for the suspect. … Gunshot wound, it looks like, to the chest, to the right side. Unresponsive. … Another gunshot wound to the buttocks.”

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