28-year-old Nicholas Robertson was fatally shot by two Los Angeles County sheriff's deputies on Saturday in a scene that was partially captured on video. The case is currently being investigated by several independent agencies, including the Sheriff's Homicide Bureau and Internal Affairs Bureau.

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Police responded to reports of a man firing a gun into the air and found Robertson walking across an intersection in Lynwood, California, a small city just outside of Los Angeles. At a press conference, Cpt. Steven Katz said that the deputies fired a total of 33 shots after Robertson failed to comply with orders to drop the gun. Both deputies have been reassigned from field duty.

"We do not have any evidence that a round was fired at deputies at this time," Katz said.

Cell phone footage of the shooting appeared on social media on Saturday, showing Robertson walking away from the deputies as they approached from their patrol cars and began shooting the suspect. One deputy fired 16 shots, and the other fired 17 shots, killing Robertson.

"He's walking away from the officers, but what's he walking to?" Los Angeles County Sheriff Jim McConnell told ATTN:. "There's a lot of factors to weigh into this. I can't say what was in the officers' minds—I don't know that, only they do—but the fact that whether or not he was a threat to them, their use of force would be based on a threat to them or someone else."

A handgun was recovered from the scene, officials said. There were no live rounds left inside the weapon. Officials provided still images from video footage that appears to show a weapon in Robertson's hand.

Los Angeles County Sheriff's Department - lacounty.gov

"In this modern age of cell phone video and instant analysis on the internet, I would ask that we keep in mind that a thorough and comprehensive investigation is detailed and time intensive," McConnell said in a press release. "It will involve, not just one source of information, but numerous sources, potentially including multiple videos, physical evidence, and eyewitness accounts."

Following the press conference, Richardson's relatives and civil rights advocates spoke out against the shooting, raising questions about the official account of the incident.

"I can understand that you have to incapacitate someone if they are a threat to you, but it appeared from the footage that he was running away, so it didn't look like they had to fire the first shots," said Keyanna Celina, a member of the Coalition for Community Control Over the Police. "But once they began shooting, it was like a firing squad and they just kept pummeling him even when he was on the ground crawling away."

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"When there's a white shooter, they always manage to apprehend him. But when there's a Black or brown suspect—or someone they suspect of a crime who even has a knife—they somehow fear for their life, even when that person is running away, and they get the firing squad," Celina added.