Prosecutors said that the officer who fatally shot a Charlotte, N.C., man in September will not be charged for the shooting, concluding that the man was armed and that the officer acted lawfully during the encounter.

The shooting of Keith Lamont Scott on Sept. 20 set off days of heated, sometimes violent protests in Charlotte, some of the most intense demonstrations seen nationwide amid an increased focus on how police use deadly force.

Andrew Murray, district attorney for Mecklenburg County, said that the recommendation from 15 career prosecutors in this case was unanimous. He also added that he had informed Scott's family of the decision earlier Wednesday.

"It was a difficult decision," Murray said during the briefing Wednesday morning. "However, the family was extremely gracious."

Police have said that Scott pointed a gun at them before Brentley Vinson, a black plainclothes officer, fired the fatal shots at him. Scott's family has disputed that he pointed a gun at the officer and whether he had a gun.

After the shooting, police released photos of a gun and ankle holster, and authorities said that gun was loaded and had Scott's fingerprints and DNA.

During the lengthy news conference, Murray pored over details from the day of the shooting, ultimately saying he had no doubt that Scott had a gun during the encounter. He also said the gun was loaded and had a bullet in the chamber.

"There's been some speculation in the community regarding whether Mr. Scott was armed," Murray said. "All of the credible and available evidence suggests that he was, in fact, armed."

In addition, police had released a photo of a "blunt" from the scene. Police have said that officers in an unmarked car in the apartment complex where the shooting occurred saw Scott, in his own car, rolling the blunt with marijuana.

Murray said Wednesday that while police said they were not going to act on the marijuana, they decided to move on Scott when they saw him raise a gun while sitting in his car.

Vinson was not wearing a recording device at the time of the shooting, police said, but the department eventually released other videos from the scene after intense pressure.

Murray said Wednesday that none of the videos showed Scott with the gun in his hand when he got out of his car, something all four officers at the scene reported seeing.

However, Murray said that videos did appear to show that Scott's pant leg was pulled up above where police said they recovered the ankle holster. During the briefing, Murray also showed surveillance video footage from the same day showing a bulge in Scott's ankle that he said was consistent with a holster and a gun.

In a recording of the shooting taken by Scott's wife, Rakeyia, she can be heard yelling at the officers that her husband was unarmed while pleading with them not to fire.

"Don't shoot him," she says in the video. "Don't shoot him. He has no weapon. He has no weapon. Don't shoot him."

Footage from a body camera worn by another officer at the scene captured part of the encounter, but it lacked audio because the officer did not activate it until after the shooting, keeping investigators and the public from learning key details about what happened before the shots were fired.

An autopsy showed that Scott had four gunshot wounds, including one to his back.

The unrest set off by Scott's death left the city reeling and struggling to return to normal. Some small protests continued after the demonstrations that garnered national media coverage, while downtown streets remained unsettled in the aftermath of peaceful protests that descended into chaos.

Scott is one of 875 people fatally shot by police officers so far this year, according to a Washington Post database tracking such shootings.

Charges against officers who shoot and kill people are rare, but this number has increased recently after waves of protests prompted by high-profile deaths involving police in New York, Baltimore, Cleveland and Baton Rouge.

Earlier this month, prosecutors in Minnesota said they were charging an officer there who fatally shot a man during an encounter partially streamed on Facebook.