A graphic incident in Los Angeles is under investigation after video emerged of a police officer beating a woman on the side of a highway. The video was recorded along the Santa Monica freeway last Tuesday during the afternoon rush hour. In it, 51-year-old grandmother Marlene Pinnock is seen being pulled to the ground and pummeled by an unidentified California Highway Patrol officer.

It's unclear what Pinnock was doing walking along the highway at the time.

"The focal point of what she did on the freeway is simple. She got beat, savagely beat by someone who seemed to be trying out for mixed martial arts. And it's unacceptable," said the woman's attorney, Caree Harper.