A white US police officer from South Carolina has been charged with murder after video emerged showing him repeatedly shooting a fleeing and apparently unarmed black man in the back.

The shooting comes in the wake of a series of similar incidents that have provoked outrage and protests, most notoriously the killing of Michael Brown in Ferguson, Missouri.

Walter Scott, 50, was shot Saturday in the city of North Charleston after a scuffle that began with his being stopped for a broken tail light in his car, local media said.

The chilling video shot in a grassy vacant lot was filmed by a passer-by who mutters expletives as he watches the incident unfold. It was later provided to the media and spread virally online.

South Carolina state police arrested officer Michael Slager, 33, and charged him with murder on Tuesday. The charge carries a sentence of up to life in prison or the death penalty.

"The defendant did shoot the victim multiple times in the back after an altercation. All this is based upon video evidence and the investigation of the State Law Enforcement Division," reads a South Carolina court document.

Scott's father, also named Walter, said the family was devastated by his son's death, but was grateful for video evidence of the killing.

"The way he was shooting that gun, it looked like he was trying to kill a deer or something running through the woods. I don't know whether it was racial or something wrong with his head or what," the father told NBC's Today Show, speaking of the charged officer.

"I thank God they had the video. God has my back. When I saw it, my heart was broken. I said, 'It can't be.' I saw it. I couldn't take it anymore."

His father said Scott may have fled because "he owed some child support and I believe he didn't want to go to jail again and he ran away."

A number of killings of unarmed black men by police officers in recent months have sparked protests -- some of them violent -- across the United States with demonstrators alleging racism in the nation's police.

Officers have rarely been charged in the shootings, even when the incidents were recorded.

In this case Slager initially says into his radio after the shooting that Scott had taken his stun gun, the Times said, quoting police reports.

However, the video shows wires from the stun gun extending from Scott's body as the two men scuffle, the Times said.

As Scott, a heavy-set man wearing black pants and a bluish-green shirt, flees, running with difficulty, Slager draws his handgun and shoots eight times toward his back. Scott falls after the last shot.

The officer later approaches Scott, who is on the ground, telling him to put his hands behind his back, and Slager puts him in handcuffs.

Slager then appears to get a device that had fallen during the altercation and drop it by Scott's body.

The video was first released by the New York Times after being given to the newspaper by the Scott family's lawyer.

North Charleston mayor Keith Summey described the shooting as a "bad decision," local newspaper The Post and Courier reported.

"When you make a bad decision, don't care if you're behind the shield or a citizen on the street, you have to live with that decision," the mayor said.

The victim's family spoke out at a news conference after the officer's arrest and called the unidentified person who filmed the video a hero.

"If there wasn't a video, would we know the truth? Or would we have just gone with what was reported earlier? But we know the truth now," said Scott's brother Anthony in remarks broadcast on MSNBC.

They remembered Scott as a Dallas Cowboys football fan and loving father of four.

Scott was hit by five bullets -- three times in the back, once in the upper buttocks and once in the ear, said family lawyer Chris Stewart, quoting the coroner who examined Scott's body, according to the Times.

The US Justice Department released a statement saying it would "take appropriate action in light of the evidence and developments in the state case."

The killing of unarmed black teen Michael Brown in August was a catalyst for a recent surge in protests in the country and a renewed debate on racism and police tactics.

A jury chose not to indict a Ferguson, Missouri, police officer for the shooting.

Since then, other killings by police have prompted protests in cities from coast to coast.

in December, two New York police officers were killed by a gunman who had boasted he was going to avenge police abuses.

Police officers have enjoyed significant legal leeway in the United States and prosecutors and civilian grand juries have often proved reluctant to indict them over excessive force.

The US Justice Department has launched investigations into a number of police departments after shootings.

It unearthed what it called damning evidence of racism in the Ferguson police department after Brown's shooting triggered unrest last year.