Story highlights The rapper was gunned down in 1996

Officer was on the scene of the shooting in Las Vegas

He asked Shakur "Who shot you?"

The first police officer at the scene of Tupac Shakur's 1996 drive-by murder has revealed the last words spoken by the late rap legend. And they're not exactly peaceful.

"He looked at me, and he took a breath to get the words out, and he opened his mouth," says Chris Carroll, a retired sergeant with the Las Vegas Metropolitan Police Department, in a new feature with Vegas Seven . "And then the words came out: 'F**k you.'"

Shakur was shot multiple times on September 7th, 1996. After leaving a boxing match with former Death Row Records CEO Suge Knight, the rapper and his bodyguards got into a scuffle with 21-year-old Crips gang member Orlando Anderson in the lobby of the MGM Grand casino. Carroll, who worked with the city's bike patrol unit, had also been watching the same Mike Tyson fight, but was unaware of the brawl taking place in the lobby.

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Later, a white Cadillac pulled up beside Knight and Shakur while they were stopped at a traffic light and one man began shooting out of the back window. Carroll was the first officer to respond to the grisly scene.

"I grab the car door and I'm trying to open it, but I can't get it open," he says. "[Knight] keeps coming up on my back, so I'm pointing my gun at him. I'm pointing it at the car. I'm yelling, 'You guys lay down! And you, get the f**k away from me!' And every time I'd point the gun at him, he'd back off and even lift his hands up, like 'All right! All right!' So I'd go back to the car, and here he comes again. I'm like, 'F**ker, back off!' This guy is huge, and the whole time he's running around at the scene, he's gushing blood from his head. Gushing blood! I mean the guy had clearly been hit in the head, but he had all his faculties. I couldn't believe he was running around and doing what he was doing, yelling back and forth."

Carroll says when he finally was able to open the door, Shakur's limp body fell out of the vehicle, "like he was leaning against the door."

"So I grabbed him with my left arm, and he falls into me, and I've still got my gun in the other hand," he continues. "He's covered with blood, and I immediately notice that the guy's got a ton of gold on -- a necklace and other jewelry -- and all of the gold is covered in blood. That has always left an image in my mind. . . After I pulled him out, Suge starts yelling at him, 'Pac! Pac!' And he just keeps yelling it. And the guy I'm holding is trying to yell back at him. He's sitting up and he's struggling to get the words out, but he can't really do it. And as Suge is yelling 'Pac!,' I look down and I realize that this is Tupac Shakur."

Carroll says he attempted to get a "dying declaration" of a potential suspect from Shakur, but the rapper was ignoring him at first.

"And then I saw in his face, in his movements, all of a sudden in the snap of a finger, he changed," he says. "And he went from struggling to speak, being noncooperative, to an 'I'm at peace' type of thing. Just like that. . . He went from fighting to 'I can't do it.' And when he made that transition, he looked at me, and he's looking right in my eyes. And that's when I looked at him and said one more time, 'Who shot you?'. . . He looked at me and he took a breath to get the words out, and he opened his mouth, and I thought I was actually going to get some cooperation. And then the words came out: 'F**k you.' After that, he started gurgling and slipping out of consciousness."

So why is Carroll coming forward with with information in 2014? Two reasons: Retiring from the Metro has allowed him the freedom to speak about the homicide case without being reprimanded ("It's been almost 18 years," he says. There's clearly never going to be a court case on this."), and he also didn't want "Tupac to be a martyr or a hero because he told the cops 'F**k you.'"

Carroll says Shakur never spoke another word -- remaining silent even when another officer tried to draw out a declaration in the ambulance.

"As soon as he got to the hospital, he went into surgery and was heavily sedated, and I guess he went into a coma and really never came out of that, until they took him off of life support," he continues. "So that moment I talked to him was his last real living moment where he was speaking. I talked to the cop who rode in the ambulance with him. He said Tupac never came out of it, and he never said anything at the hospital. There was nothing else."