According to a police statement, the girl was groped and then confronted a man she accused of doing it. Video shows she punched him and then was pepper-sprayed in the face. The police department says it's "currently looking for two suspects, one for the sexual assault and one for the pepper spray."
The protest was planned before Trump's rally took place in Janesville. According to the Facebook event page, more than 1,000 people said they were going. The organizer stressed the event was meant to be peaceful, saying, "Violence will not be tolerated!"
Interactions between Trump supporters and anti-Trump protesters have turned increasingly violent in recent weeks. Trump's rivals have blamed the "culture of violence" the candidate creates.