VIDEO: Cop Beats Lesbian Teen at Pittsburgh Pride

What happened at Sunday's Pittsburgh Pride event? A video shows a young woman being thrown around and punched several times by a police officer, who then arrested her and slapped her with charges that include resisting arrest.

But witnesses contend Ariel Lawther did not challenge or attack the cop, only stood her ground. The officer in question, now on desk duty, initially went to break up an altercation between Lawther and an antigay protestor. In the video below, Lawther's fiancee is screaming at the officers as he violently arrests Lawther. After her arrest, the teenager posted her $5,000 bail and was released.

In a news conference, Pittsburgh mayor Bill Peduto promised an investigation into the incident, which is sparking outrage across the internet. Adding to the mystery of what happened, WPXI reports Lawther apologized to the officer after the arrest.