Tupac Shakur Knew Who Killed Him According to New 'Snapped' Documentary

Tupac Shakur knew who killed him but his murder remains unsolved because the Las Vegas PD never wanted to solve it ... according to a new 2Pac special, and TMZ has the exclusive first clip.

Pac's getting his own 'Snapped: Notorious' documentary on Oxygen airing September 10. It'll run 2 hours with in-depth interviews from people who were the last to see him alive before he was fatally shot dead in a drive-by in 1996. They include close friends and rappers Danny Boy and Yo-Yo, DJ Mister Cee, Pac's first manager Leila Steinberg, music journalist Toure and others.

The trailer, obtained by TMZ, paints a vivid picture of Pac's last breaths on his deathbed in a Las Vegas hospital ... his finger shot off and nodding that he knew who did this to him.

A must watch for any 2Pac fan.