A 24-year-old Portland man has been sentenced to five years, 10 months in prison for hitting another man over the head with a baton during a downtown Portland demonstration last summer that turned violent.

Gage Halupowski received the sentence Friday in Multnomah County Circuit Court after pleading guilty to second-degree assault.

Halupowski wore a mask and black clothing during the June 29 attack on Adam Kelly, but a Portland police officer witnessed the attack and with other officers made the arrest.

Members of the so-called Proud Boys, a far-right-wing organization, and an anti-fascist group called Rose City Antifa held dueling protests. Fights broke out when the groups crossed paths.

Adam Kelly was a right-wing protester who police say attempted to help another person under attack when he was attacked.