Sources told the outlet that a man grabbed a woman, who could have possibly been his ex-girlfriend, by the throat and refused to let her go.
Bieber attended the event with a friend. The incident erupted as he was talking to other guests, when the attacker apparently "went ballistic." Bieber and the friend repeatedly told the guy to let her go; when he refused by screaming, "Go fuck yourself," Bieber hit him, freeing the woman from his grasp.
Some claim the man who grabbed the woman was on the drugs. He was reportedly seen later chasing down an SUV he believed the singer was inside. He was later arrested by local authorities.
Of course, the alleged altercation wasn't Saturday's main story. Coachella became #Beychella as Beyoncé recruited Jay Z, Destiny's Child, and Solange to join her on stage.