One of the last living witnesses to the fatal drive-by shooting of rapper Tupac Shakur in Las Vegas has been charged with murder with use of a deadly weapon over the 1996 killing.

The charges against Duane “Keffe D” Davis on Friday represent a long-awaited breakthrough in a case that has frustrated investigators and fascinated the public ever since the hip-hop icon was gunned down 27 years ago.

Chief Deputy District Attorney Marc DiGiacomo said a grand jury that indicted Davis in Nevada 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, 60, was arrested on Friday morning while on a walk near his home, according to DiGiacomo.

Davis has long been known to investigators in the United States and has himself admitted in interviews and in his 2019 tell-all memoir, Compton Street Legend, that he was in the Cadillac from which the gunfire erupted during the September 1996 drive-by shooting.

Shakur was 25 when he was killed.

Las Vegas police raided a home in mid-July in the Las Vegas suburb of Henderson that is tied to Davis.

Police were looking for items “concerning the murder of Tupac Shakur”, according to the search warrant. They collected multiple computers, a mobile phone and hard drive, a Vibe magazine that featured Shakur, several .40-calibre bullets, two “tubs containing photographs” and a copy of Davis’ memoir.

Clark County District Judge Jerry Wiese denied Davis bail.

“It has often been said that justice delayed is justice denied,” District Attorney Steve Wolfson said after the hearing in a brief comment to The Associated Press news agency. “In this case, justice has been delayed, but justice won’t be denied.”

It was not immediately clear if Davis has a lawyer who can comment on his behalf. Davis has not responded to multiple phone and text messages from AP seeking comment or an interview in the more than two months since the house raid.

Shakur 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 at the age of 25.

The rapper’s death came as his fourth solo album, All Eyez on Me, remained on the charts, with some five million copies sold. Nominated six times for a Grammy Award, Shakur is still largely considered one of the most influential and versatile rappers of all time.

In his memoir, Davis said he was in the front passenger seat of the Cadillac and had slipped the gun used in the killing into the backseat, from where he said the shots were fired.

Davis implicated his nephew, Orlando “Baby Lane” Anderson, saying he was one of two people in the backseat. Anderson, a known rival of Shakur, had been involved in a casino brawl with the rapper shortly before the shooting.

After the casino brawl, “Mr Davis formulated a plan to exact revenge upon Mr Knight and Mr Shakur” in his nephew’s defence, DiGiacomo said.

Anderson died two years later. He denied any involvement in Shakur’s death.

Davis revealed in his memoir that he first broke his silence 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 them about Tupac’s killing, as well as the fatal shooting six months later of Tupac’s rap rival, Biggie Smalls, also known as the Notorious B.I.G.

“They offered to let me go for running a ‘criminal enterprise’ and numerous alleged murders for the truth about the Tupac and Biggie murders,” he wrote. “They promised they would shred the indictment and stop the grand jury if I helped them out.”

At the time of their deaths, Shakur and Smalls 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 was not surprised by Davis’s arrest.

The former 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 memoir.

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