R&B singer The Weeknd was arrested Saturday in Las Vegas ... after he was accused of punching a cop.
Law enforcement sources tell us a fight allegedly involving Weeknd started inside the Cromwell Hotel around 4:20 AM ... and when they arrived, the fight was still raging.
We're told cops attempted to break up the fight, and one of them pulled the singer into an elevator during the scuffle. That's when Weeknd allegedly punched him in the head.
I've always been confused as to how a sane person could ever bring himself to a place where he believes that that haircut is an alright thing to do. Maybe he's a little off..
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