A Hayward woman is facing criminal charges, but insists it is the officer who should be facing consequences.

Carolina Olvera says she is the victim of police brutality after she and her friends were pulled over by Hayward police. The incident occurred two weeks ago and Olvera, 19, says she has video to back up her claims.

"I'm angry, I'm hurt," she said.

Olvera said she is traumatized by the unexpected encounter with police that left her battered and bruised.

Police said they had a warrant for one of the passengers with Olvera for an armed carjacking. Olvera said she did not know that, and got out with her hands up, but was scared.

Olvera said an officer slammed her head against the patrol car, cutting her lip. When she spit out blood she said the officer grabbed her again.

"He grabbed me from my hair and you see him slam me against the cement floor," she said.

A witness caught the incident on camera.

Once on the ground injured, Olvera said she instinctively began to struggle.

"I was in shock. I was in shock," she said. "I was already in pain and they had their knees on my back."

Hayward police said use of force is not pretty, but sometimes necessary. An internal investigation is now underway.

"At the conclusion of the investigation if there are any improprieties, any wrongdoings located or discovered, our officer will be held accountable," said Guy Jakub with the Hayward Police Department.

Olvera, who bakes custom order cakes for a living, said she has never had a run-in with police before and cannot shake what happened.

"I want an apology and I want them to fix their department," Olvera said. "I want them to train their officers better because this cannot happen to anybody else."