Santos, an award-winning photojournalist who has covered major news events from Haiti to the Middle East, said he was sent Tuesday to the Manhattan city clerk's office, where Baldwin and his fiancee, yoga instructor Hilaria Thomas, were filing for a marriage license, only because he was on assignment in the neighborhood.
"I'm a news photographer. I don't usually do celebrities," he said.
Instead of a happy shot of the couple leaving the clerk's office, what has made headlines is a photograph of Baldwin lunging at Santos. Baldwin, 54, has said he was the one targeted, and that Santos was "aggressively trying to shoot" him and Thomas.
"I saw him come out of the court, and we started taking his picture," Santos said. "Next thing I saw him go after the other photographer. I looked at him and said, 'Don't touch him.' Next thing I saw he looked at me and came right at me. I didn't have time to react.
"The camera sometimes does not get everything," Santos said of the widely circulated photograph, which Baldwin has used to say he was the victim. "Look at the angle, because you cannot see because I was like this [sideways]. You see the punch and the punch landing. I'm moving back. He hit me before. I was trying to move back to soften the blow. He just lunged at me."
Santos filed a complaint against Baldwin Tuesday, and said he was suffering from headaches and a sore jaw as a result of the alleged assault. He spent two hours Wednesday in the office of the Manhattan District Attorney and, according to his attorney, wants to see Baldwin prosecuted.
"He wants justice, and that means he wants Baldwin held accountable for what he did," Sanford Rubenstein, Santos' attorney, told "GMA." "What he wants very simply is to see him prosecuted for what he did so it doesn't happen to anyone else."
"The two other photographers who were on the scene when this happened have been interviewed by prosecutors, and they're cooperating also," Rubenstein said. "His [Santos'] medical records are available to the prosecutors."
Sources close to Baldwin previously told ABC News that the actor was keeping his options open about the possibility of filing his own assault claim. He has been characteristically outspoken about the incident since it occurred, venting on Twitter and appearing on TV to tell his side of the story, most recently joking about it with David Letterman.
"I think you can see, I'm forming the letter 'F' with my mouth," Baldwin said to Letterman Wednesday night in an appearance on his show. "And what I'm saying is, I said to him as I walked up to him, 'What F-stop are you on with the camera?' And he said, 'I'm on a something,' and I said, 'That's not the F-stop. … You have to set the camera on the right F-stop.'"
Santos did not directly address Baldwin's latest remarks and said he would remain similarly silent if he ever saw the actor in person again.
"I have nothing to say to him," Santos said. "I'm just feeling embarrassed about what he did to me. I like to take a picture and have my picture be on the front page, not me be on the front page. I don't want to be a part of the news."