Tensions remain high in Portland, Oregon, one of the centres of widespread national civil rights protests last summer, after a far-right rally on Sunday commemorating a past clash turned violent itself.

Hundreds of people, including far-right street fighters from the Proud Boys gang and anti-fascist demonstrators, fought in the streets of Northeast Portland, using mace, pepper spray, paintball guns, clubs and mortar fireworks as weapons.

A 65-year-old was arrested on Sunday evening after firing a handgun at what appeared to be a group of anti-fascists, and was charged with unlawful possession and use of a weapon.

Earlier in the week, city officials warned they might not directly intervene in expected clashes.

“We are dedicated to keeping the peace. Our ask is simple: We are asking you to choose love,” Mayor Ted Wheeler said on Friday during a press conference. “People should not necessarily expect to see the police standing in the middle of the crowd trying to keep people apart. People need to keep themselves apart and avoid physical confrontation.”

A mayoral spokesperson told Oregon Public Broadcasting (OPB) the police were aware of the clashes “within minutes” and planned to make arrests after the fact.

Violence continued into the early evening on Sunday. Proud Boys flipped over and defaced a van that pulled into a parking lot near their event, and ransacked a truck believed to belong to a left-wing protester, who himself received numerous injuries. Anti-fascists also reportedly harassed and attacked local journalists.

“I saw this dude beating a woman,” a witness, who asked to remain anonymous, told OPB of the van. “There was like two ladies that got hit. It was a nightmare, it was f****** terrifying.”

As the chaos continued, Proud Boys appropriated a Black Lives Matter slogan, chanting, “Whose streets? Our streets!”

The event began at an ironically named far-right event honouring the “Summer of Love,” last year’s protests in Portland which often featured violent clashes between left- and right-wing groups amid broader, peaceful civil rights activism.

“We’re not going to stand down,” Proud Boy Tusitala “Tiny” Toese told the crowd from a makeshift stage, warning the group was “not playing this time.”

Last summer, Portland became one of the epicentres of the Black Lives Matter protests that swept the nation, and Donald Trump sent scantily identified federal troops to crack down on activists, including pulling them into unmarked vans.