Users believe Cesar Zavala is the man who beat up a girl, Shelby Elston, at Rufus Du Sol's show in Pasadena [VIDEO]

In the viral video, Cesar Zavala is seen brutally assaulting Shelby Elston, who is bleeding.

Concertgoers captured the alleged attack on camera, and the victim, Shelby Elston, uploaded it on Facebook. Elston, who went from Phoenix, Arizona to Pasadena, California for the concert, is now asking for the public's assistance in identifying the attacker.

She wrote that her companion inadvertently splashed a drink on the man, who was seated in front of them in Section 12-H, shortly after they arrived. Despite immediate apologies, the irate man left and returned about 30 minutes later, at which point he began screaming threats of violence.

“That is the last thing I remember before waking up in the medical tent an hour later,” Elston wrote.

Elston said the man repeatedly punched her in the face and knocked her unconscious, then attacked her male friend as another tried to intervene.

“I was completely knocked out and there was blood pouring from my face,” she recalled.

The man fled into the crowd and has not been apprehended, according to Elston, who received treatment onsite from the venue’s medical staff and missed the entire concert.

Elston claims she was “traumatized from what happened.” She has filed a police report and intends to press charges, she wrote on Reddit.

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