Justin Bieber's pals Lil Za and Lil Twist acted like Lil Thugs by attacking a paparazzo in Miami last June -- so claims the photog who's suing Bieber and a bodyguard.
Photog Jeffrey Binion says in his depo -- obtained by TMZ -- he was confronted by Za, Twist and 2 of Justin's bodyguards after taking pics of Justin outside of a recording studio.
Binion says Za demanded the photog's camera ... threatened to break it ... then tried to wrench it from his hand. Binion claims the struggle lasted 3 to 5 minutes. As for Twist ... Binion says he was egging Za on.
Binion also claims one of the bodyguards threatened him with a gun.
Binion says he was strong armed into deleting the photos ... because a bodyguard had him in a choke hold.
He's now suing Bieber and that bodyguard ... claiming he's injured and mentally screwed up.
Bieber is scheduled to give his version in a deposition next month ... and he's already asked a judge to keep his testimony under wraps -- away from the public.