One of the last living witnesses to the fatal drive-by shooting of rapper Tupac Shakur in Las Vegas has been charged with his long-unsolved 1996 murder. Law enforcement officials announced Friday that 60-year-old Duane "Keffe D" Davis is charged with one count of murder with use of a deadly weapon with a gang enhancement. 

The long-awaited break comes in a case that has frustrated investigators and fascinated the public ever since the hip-hop icon was gunned down on the Las Vegas Strip 27 years ago.

A Nevada grand jury indicted Davis in the killing, prosecutors revealed in court Friday morning. CBS Las Vegas affiliate KLAS confirmed news of the indictment, which was first reported by The Associated Press.

"Many people who did not believe the murder of Tupac Shukar was important to this police department, I am here to tell you: that was simply not the case," Sheriff Kevin McMahill said at a news conference Friday afternoon.

"Our goal was always to hold those responsible for Tupac's violent murder accountable," he said.

"This case has been reviewed by our homicide team and our homicide detectives for over two and a half decades, and our persistence in this investigation has paid off," said Las Vegas Metropolitan Police Department homicide Lieutenant Jason Johansson. 

He described Davis as "the leader and shot-caller of the South Side Compton Crips," and said the groups had been involved in "an ongoing feud."

Chief Deputy District Attorney Marc DiGiacomo said a grand jury had been seated in the case for "several months." DiGiacomo described Davis as the "on-ground, on-site commander" who "ordered the death" of Shakur.

The charges were revealed hours after Davis was arrested Friday morning while on a walk near his home, according to DiGiacomo. 

Davis has been known to investigators and has also admitted in interviews and in his 2019 tell-all memoir, "Compton Street Legend," that he was in the Cadillac where the gunfire erupted during the September 1996 drive-by shooting. 

The arrest comes two months after Las Vegas police raided his wife's home in Henderson on July 17. Documents said police were looking for items "concerning the murder of Tupac Shakur."

Police reported collecting multiple computers, a cellphone and hard drive, a Vibe magazine that featured Shakur, several .40-caliber bullets, two "tubs containing photographs" and a copy of Davis' 2019 tell-all memoir, "Compton Street Legend."

In the book, Davis said he broke his silence over Tupac's killing in 2010 during a closed-door meeting with federal and local authorities. At the time, he was 46 and facing life in prison on drug charges when he agreed to speak with the authorities.

"They promised they would shred the indictment and stop the grand jury if I helped them out," he wrote.

He has described himself as one of the last living witnesses to the shooting.

KLAS reports it was unclear Friday why the case was suddenly moving ahead after more than two decades. Las Vegas police previously said that a 2018 interview Davis gave to BET prompted them to review the case.

Davis admitted publicly in the 2018 interview for a BET show to being inside the Cadillac during the attack, and implicated his nephew, Orlando "Baby Lane" Anderson, as one of two people in the back seat where the shots were fired.

"When we pulled up, I was in the front seat," Davis said in the 2018 BET interview."Happen to see my friend, Suge."

"You said the shots came from the back," the interviewer asks Davis in the BET video. "Who shot Tupac?"

"Going to keep it for the code of the streets," Davis said. "It just came from the backseat, bro."

Shakur was 25 when he was gunned down in the drive-by shooting near the Las Vegas Strip on the night of Sept. 7, 1996. The rapper was in a BMW driven by Death Row Records founder Marion "Suge" Knight in a convoy of about 10 cars. They were waiting at a red light when a white Cadillac pulled up next to them and gunfire erupted. Shakur was shot multiple times and died a week later.

The shooting happened shortly after a casino brawl earlier in the evening involving Anderson, Shakur and others. Anderson denied any involvement in the Shakur shooting. He died two years later in a shooting in Compton, California.

Shakur's death came as his fourth solo album, "All Eyez on Me," remained on the charts, with some 5 million copies sold. Nominated six times for a Grammy Award, Shakur is largely considered one of the most influential and versatile rappers of all time. Shakur was feuding at the time with rap rival Biggie Smalls, also known as the Notorious B.I.G., who was fatally shot in March 1997. At the time, both rappers were in the middle of an East Coast-West Coast rivalry that primarily defined the hip-hop scene during the mid-1990s.

Greg Kading, a retired Los Angeles police detective who spent years investigating the Shakur killing and wrote a book about it, said he would not be surprised by Davis's indictment and arrest.

"It's so long overdue," Kading told The Associated Press during a recent interview. "People have been yearning for him to be arrested for a long time. It's never been unsolved in our minds. It's been unprosecuted." 

Kading said he interviewed Davis in 2008 and 2009, during Los Angeles police investigations of the killings of Shakur in Las Vegas and the slaying of Biggie Smalls. 

Kading said he also talked with a Las Vegas police detective about the case, including after the SWAT raid in July at the home in Henderson.

The former Los Angeles police detective said he believed the investigation gained new momentum in recent years following Davis's public descriptions of his role in the killing, including his 2019 tell-all memoir, "Compton Street Legend."

"It's those events that have given Las Vegas the ammunition and the leverage to move forward," Kading said. "Prior to Keefe D's public declarations, the cases were unprosecutable as they stood."

"He put himself squarely in the middle of the conspiracy," Kading said of Davis and the Shakur slaying. "He had acquired the gun, he had given the gun to the shooter and he had been present in the vehicle when they hunted down and located both Tupac and Suge (Knight)."

Kading noted that Davis is the last living person among the four people who were in the vehicle from which shots were fired at Shakur and rapper Marion "Suge" Knight. Others were Davis's nephew, Orlando "Baby Lane" Anderson, Terrence "Bubble Up" Brown and DeAndre "Freaky" Smith.

"It's a concerted effort of conspirators," Kading said, adding that he believed because the killing was premeditated Davis could face a first-degree murder charge.

"All the other direct conspirators or participants are all dead," Kading said. "Keefe D is the last man standing among the individuals that conspired to kill Tupac."