North Charleston police officer Michael Slager is seen allegedly shooting 50-year-old Walter Scott in the back as he runs away in this still image from video in North Charleston, S.C., taken Saturday. NBC News identified the witness who filmed the shooting as Feidin Santana. Reuters

After NBC News identified Feidin Santana Wednesday night as the eyewitness who recorded the fatal shooting of Walter Scott, Twitter exploded with compliments and concern. While some users praised Santana for releasing the video, others posted messages calling for his protection. They feared retribution from people angered by his recording.

Santana is credited with changing the narrative around Scott's Saturday death. Officer Michael Slager said he opened fire on the unarmed black man in self-defense. After the release of Santana's video showing Scott being shot repeatedly as he runs away, Slager was charged with murder and fired from the police force.

Santana said he was walking to work when he saw the men struggling. He hit record after they got up from the ground. Later he gave the video to the family and media. “When I turned it in, I thought about their situation and said if I were to have a family member where that happened I would like to know the truth," Santana told NBC.

Scott family lawyer L. Chris Stewart said at a news conference that Santana's actions “should be respected throughout this country," according to the Guardian. "We have to really recognize the strength and fortitude and fearlessness that it took to come forward when you know you just filmed a police officer murder somebody," Stewart said.

Many Twitter users agreed.

Several users worried Santana could end up in a situation similar to that of Ramsey Orta, the 23-year-old who filmed as Eric Garner was choked by a Staten Island, N.Y. officer last summer. Orta has been arrested twice since the incident. He told reporters in August that he was "100 percent sure" the police were targeting him.

Santana said the officer made a bad decision in shooting Scott. "Mr. Scott didn’t deserve this, and there were other ways that can be used to get him arrested, and that wasn’t the proper way to do that," he said.