L.A. rapper Saviii 3rd won't be getting tricks or treats on Halloween, instead, he'll be in court for an arrest -- cops say he bolted out of a studio session with over $3,000 worth of equipment.
Burbank police sources tell TMZ Hip Hop ... Saviii was recording inside Royal Rehearsal studio Wednesday night before he allegedly stole a speaker, mic, mac hard drive and a monitor ... and a few other pieces of equipment.
We're told officers detained the ex-Cash Money Records artist and his entourage in the back of the studio's parking lot. Saviii, whose government name is Tyrus Washington, identified himself as Johnnie Lee Brown ... according to cops.
The fake name didn't help ... police searched Saviii and say they found what they believe to be methamphetamine on him. They also allegedly found codeine cough syrup, evidence of identity theft and the studio equipment.
Saviii was arrested and booked into Burbank jail. They didn't discover the fake name until they fingerprinted the rapper, and they also found an active warrant for a probation violation under his real name.
Before his arrest, Saviii's final Instagram story shows a bottle of Wockhardt promethazine codeine and several bottles of Faygo soda. It's unclear if these are the bottles cops allegedly found in his car.
The investigation is ongoing, and Saviii's due in court on October 31. No costume required.