Following news that the found handgun that was used to kill Tupac Shakur 19 years ago has since disappeared, the detective who worked on the case says he knows where the gun is at.

Retired LAPD Detective Timothy Brennan, who worked on the 2Pac murder case, told TMZ that he ordered ballistic testing on the weapon. He claims he gave the gun to ATF agents who conducted the testing. Once it came up a match, in a federal law enforcement database, he says ATF sent it to Las Vegas cops.

But in a strange twist, Brennan says LVPD didn't believe it was a match and rejected the weapon. According to Brennan, the protocol after that is to send the gun back to LAPD. So for him, the Los Angeles authorities have the weapon. But if the LAPD is saying they don't have the handgun, then Brennan suspects foul play.

In addition, TMZ also discovered that the alleged murder weapon was found one day after 2Pac's presumed killer, Orlando Anderson, was killed. Anderson was a known member of the Southside Crips and was killed during a gang shootout on May 29, 1998. The .40 caliber Glock used to shoot and kill 2Pac was found on May 30 in Compton, Calif.

News of this alleged murder weapon will be explored on A&E's docu-series Who Killed Tupac?. The final episode will air on Tuesday (Dec. 19).

Watch a Preview of A&E Docu-Series Who Killed Tupac?

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