As far back as 1998, Duane Keith Davis was telling a cable channel that he was a front-seat passenger in a car from which a fellow passenger fired the shots that killed Tupac Shakur.

In 2009, Davis, known as "Keffe D," confessed to police a role in the case, a former detective who investigated the shooting told CNN, but authorities couldn't immediately use the information.

And then after what police say was a reinvigorated investigation, Davis, 60, was arrested in Las Vegas on Friday, with a grand jury indicting him in the case on charges of murder with use of a deadly weapon. The arrest comes some 27 years after the rapper was shot as he was leaving a boxing match on the Las Vegas Strip.

The shooting on September 7, 1996, was a retaliatory attack on the 25-year-old star, police said Friday. Authorities allege Davis plotted and orchestrated the shooting in a matter of hours, after the rapper and others attacked Davis' nephew that same day.

Davis is the only suspect in the case who still is alive, police say. Davis has said in a memoir that he's one of two living witnesses -- with the other being a record-label boss who was driving Shakur.

"Over the last five years, we've conducted countless interviews and corroborated numerous facts that were not only consistent with the crime scene on the night of the incident, but also corroborated and were consistent with the sequence of events that night," Jason Johansson, a Las Vegas police homicide lieutenant, said during a news conference Friday.

Here's what we know about Davis, what led up to the shooting and his indictment and arrest.

Davis was 'the shot caller,' police say

Shakur's shooting stems from a conflict between two gangs based in Compton, California, police said Friday.

Shakur and Marion "Suge" Knight, then the CEO of the rapper's label Death Row Records, were affiliated with the Mob Piru gang in Compton, Johansson said. Davis was affiliated with the Southside Compton Crips, he added.

Shakur was in Las Vegas to attend a Mike Tyson boxing match at MGM Grand Hotel -- an event that Davis and his nephew Orlando Anderson also attended.

After the match, members of Death Row Records saw Anderson near elevator bank inside the hotel, approached him and began kicking and punching him, Johansson said Friday during the news conference, where he showed hotel surveillance footage of the altercation. Shakur and Knight were visible among the men who attacked Anderson.

Both crews left the hotel after the fight, with Shakur and his group headed to a post-fight party at a nightclub.

When Davis learned of the attack on his nephew, Davis "began to devise a plan to obtain a firearm and retaliate against Suge Knight and Mr. Shakur," Johansson said.

After securing a gun "from a close associate," Davis got into a white Cadillac with Terrence Brown, Deandre Smith and Anderson, Johansson said. While in the car, Davis handed the gun "to the passengers in the rear seat of the vehicle," Johansson said.

Eventually, the group tracked down the car Shakur and Knight were in, drove alongside their black BMW, and gunshots were fired from the Cadillac into the BMW, striking Shakur four times, authorities said. The rapper died six days later.

"Duane Davis was the shot-caller for this group of individuals that committed this crime. He orchestrated the plan that was carried out to commit this crime," Johansson said.

Anderson and Smith were both in the back of the Cadillac, according to the indictment against Davis, but it does not specify who pulled the trigger. Anderson denied involvement in the killing to CNN before his death in a gang-related shooting in 1998.

Knight is in prison on a manslaughter charge in an unrelated case.

Davis placed himself at crime scene

In a 1998 interview with BET, Davis said he was in the front seat of the car from which the shots were fired.

"Going to keep it for the code of the streets," Davis replied when asked who pulled the trigger. "It just came from the back seat, bro."

Then more than a decade later, Davis confessed to police a role in the shooting in 2009, said Greg Kading, a former police detective who investigated the case.

But his statement could not be used as evidence because it was made under a "proffer agreement," Kading told CNN on Friday. A proffer is an agreement in which a suspect agrees to provide potentially useful information in an investigation, but the statements made generally cannot be used as evidence against the suspect.

Additionally, a memoir penned by Davis -- a copy of which was seized in July during a police search of the Nevada home of Davis' wife -- describes Davis and Knight as the only two living witnesses to Shakur's shooting.

Items seized in July search

During the search of the home, police seized several tablets, an iPhone and five computers. Authorities also took USB and hard drives, photographs and a copy of a magazine issue about Shakur.

At the time, police were looking for "notes, writings, ledgers, and other handwritten or typed documents concerning television shows, documentaries, YouTube episodes, book manuscripts, and movies concerning the murder of Tupac Shakur," an affidavit requesting a search warrant stated.

Davis 'talked himself right into jail'

The decades-old case gained renewed focus in 2018, particularly because Davis was talking about it publicly, and the emergence of new information, officials said.

"Davis' own admissions to his involvement in this homicide investigation that he provided to numerous different media outlets" helped reignite the investigation, Johansson said Friday.

Davis participated in a 2018 Netflix documentary on the Shakur homicide, and released his memoir in 2019.

"He began to go out publicly boast about his involvement in the murder, and that led to law enforcement in Las Vegas taking another look at his claims, and ultimately, he's talked himself right into jail," Kading, the former detective, told CNN.

"This was likely our last time to take a run at this case to successfully solve this case and bring forth a criminal charge," Johansson said.