Trying to find this movie...Please Help

Does anyone know the name of the movie, im thinking mid to late 90's, the most outstanding thing i can remember is that this alien possibly a bounty hunter is in this bar and fires a magnetic disc weapon out of a wrist gauntlet that bounces off the walls and slices a bunch of guys throats, and when a cop is investigating later he finds it stuck in a speaker in the bar? Also, somethin about the bad alien using some component of human blood to make some kind of drug maybe...not sure. I would really appreciate any help on this.