South Carolina Cop charged with Murder in videotaped killing of unarmed black man; (WARNING: GRAPHIC CONTENT)

A white cop in South Carolina was charged with murder on Tuesday, hours after a cell phone video revealed he shot a fleeing black man in the back during a routine traffic stop, contradicting an account he gave of the Saturday shooting.

The Mayor of North Charleston announced the charges against officer Michael Slager after a witness turned over the disturbing footage to authorities.

“When you're wrong, you're wrong," Mayor Keith Summey said at a news conference on Tuesday. "And if you make a bad decision, don't care if you're behind the shield or just a citizen on the street, you have to live by that decision."

The South Carolina Law Enforcement Division is leading the investigation into the shooting. The Department of Justice has announced the FBI will investigate the incident and provide any assistance needed in the state's probe.

The officer was booked into the Charleston County Detention Center. If convicted, Slager could face the death penalty or a minimum of 30 years in prison.

Slager was denied bail Tuesday night following his arrest. An ultra-conservative group, Culture Fight, initially launched an online fundraiser to pay for the patrolman's legal defense but the page disappeared in less than two hours.

The deadly confrontation reportedly began about 9:30 a.m. Saturday. Slager claimed he pulled over Scott for a broken taillight and opened fire after Scott took his Taser. He said he feared for his life during a struggle with the 50-year-old Scott.

Scott is seen in the video sprinting from the officer and appears to clear at least 15 feet before Slager fires the first of eight shots. Dressed in a green shirt and jeans, Scott stumbled and then crumpled face first into the grass.

"Shots fired," Slager said into his radio as he closed in on Scott.

"Put your hands behind your back!" the officer shouted as he circled the body with his gun drawn.

Slager cuffed Scott's hands before jogging back to his original position where he appeared to pick something off the ground. Another officer arrived as Slager returned to Scott and tossed an object, apparently the stun gun, next to the body.

The shocked witness continued to film as Slager leaned down to check Scott's pulse more than three minutes after the deadly shooting. The witness has yet to be identified.

Five of the eight shots hit Scott, according to his family’s attorney — four in the back and one in the ear.

“Every time I close my eyes, all I see is my brother taking those bullets,” Scott’s younger brother, Rodney, told the Post and Courier. “I can’t sleep.”

An attorney representing the officer had released a statement on Monday, claiming the veteran patrolman was frightened because Scott tried to grab his stun gun. The lawyer said Tuesday Slager wasn't his client anymore.

Lawyers for the Scott family lauded Tuesday's developments but criticized police for initial accounts of the fatal encounter that relied on Slager's version of events.

"Where would we be without that video?" attorney Justin Bamberg at a news conference with Scott's relatives and the National Action Network on Tuesday night.

It's only because of the "hero" who filmed the shooting that they know what really happened, Bamberg added.

"You have to recognize the strength and fearlessness and fortitude it took to come forward when you realize you've just recorded a police officer murder somebody," he said of the witness.

North Charleston Police Chief Eddie Driggers called the shooting a "tragic event" that wasn't representative of the department, which employs 343 officers in a city with a population that is nearly 50 percent black.

Gov. Nikki Haley said in a statement the case “is not acceptable in South Carolina, nor is it reflective of our values or of the way most of our law enforcement officials acts, and I assure all South Carolinians that the criminal judicial process will proceed fully.”

Scott had several previous arrests connected to contempt of court charges for failing to pay child support, and he had one assault and battery charge in 1987, the Post and Courier reported.

Scott's relatives remembered him as an "outgoing" father of four who served two years in the U.S. Coast Guard before being honorably discharged. He was engaged at the time of his death.

"I have two brothers — I had two brothers," Anthony Scott said, pausing as tears welled in his eyes. "Now I have one brother."

The distraught sibling called for policing reforms to prevent more tragedies and asked supporters to remain peaceful as the investigation continues.

"All we wanted was the truth," Anthony said.

Slager was also a Coast Guard veteran, and had been on the North Charleston force for five years. Two people had filed complaints against him during that time, including one man who said Slager shot him with a Taser in 2013 for no apparent reason, the Post and Courier reported. Slager was never charged for that complaint.