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PORTLAND, Ore. – A 22-year-old man suspected of placing burning road flares inside a Target store and a police car during a May Day riot in downtown Portland confessed to the crimes, according to court documents.

Portland police arrested Damion Zachary Feller on Wednesday and booked him into the Multnomah County Jail on charges of first-degree arson, second-degree arson, criminal mischief and riot.

Feller agreed to meet with detectives, who showed him photos of the man who threw the flares, and Feller responded by saying, "I saw that online and I knew I was fucked," court documents said.

Feller admitted to throwing a flare into the Target store and another into a police vehicle. He said he threw the flares, "Because I am a fucking idiot," and said his actions were based on a "mob mentality," according to court documents.

Video from Monday’s riot as well as community tips helped police identify Feller as the suspect. Investigators seized evidence linking him to the crimes, police said.

Damage to the Target store and police vehicle exceeded $1,000 each.

Twenty-five people were arrested on Monday after a permitted May Day march turned into a riot. Damage, including broken windows, was reported at multiple downtown locations.

Photos: May Day 2017 riot in Portland

Feller was arrested for disorderly conduct and reckless burning in March during a protest over the fatal police shooting of Quanice Hayes. He was seen burning a flare outside the Portland Building during that protest, police said.