The late Tupac Shakur was killed over 20 years ago, and there has been little to no progress made in finding his killer. The cable channel A&E has been airing the special, Who Killed Tupac? The show investigates his case with hopes of finding out who was behind his murder.

The original handgun that was used to kill Tupac was allegedly found in a Compton backyard 19-years ago, but has since disappeared. No one in law enforcement knew what happened to it, or who had the weapon in their possession last.

In the docu-series, Who Killed Tupac? a .40 caliber Glock was found by a citizen in his backyard in 1998. The findings were reported to police and Compton records show that it was booked and in their possession on May 30, 1998.

In 2000, L.A. County Sheriff's Dept. took over law enforcement of Compton, and 3,800 confiscated firearms–including that Glock were transferred to the LASD. In 2006, Deputy T. Brennan, the same deputy that was working on Notorious B.I.G. murder, found the address of where the gun was first found, and it was the home of a prominent Crip member who Tupac had a well-known beef with.

A ballistics test is ordered and the results matched as the firearm that was used to kill Tupac. The information was revealed on the show that the firearm was never reported to the Las Vegas police department. The federal prosecutor assigned to the case stated there were concerns the discovery of the gun might incite more violence.

Civil rights attorney Benjamin Crump told Tupac's brother the news of the discovery, and he was in total shock. A&E has stated they reached out to LVPD, and some officers said they never received the weapon, while others are not sure. One thing that is certain— the firearm was found by police but later disappeared.

Watch the clip below of Tupac's brother finding out the news of the weapon.

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