A Hillary Clinton supporter attacked a Donald Trump supporter and lit a flag on fire at a Clinton-Kaine campaign event in downtown Pittsburgh on Saturday, according to CBS Pittsburgh.

According to a criminal complaint, Joshua Sturman was in downtown Pittsburgh to support Hillary Clinton and attend her rally. Sturman crossed a downtown street and walked into the middle of a group of Trump supporters, who had gathered on the opposite sidewalk and were peacefully protesting Hillary Clinton.

Sturman then pulled out a flag and began to light it on fire. The Trump supporters attempted to put out the fire, which “enraged” Sturman. Sturman then grabbed a Trump supporter, threw him to the ground, and attempted to jump on top of him. Trump supporters and other bystanders alerted nearby police officers who removed Sturman and arrested him.

The Trump supporter who was attacked told police he was afraid the flag had been doused in accelerant.

Sturman is being charged with disorderly conduct, simple assault, recklessly endangering another person, and causing or risking catastrophe.

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