A May Day march in Portland, Ore., "devolved into a full-scale riot with random acts of vandalism" by anarchists late Monday, police say. Attacks on police and emergency personnel resulted in 25 arrests.
Molotov cocktails, smoke bombs and other items were thrown at police, according to member station Oregon Public Broadcasting.
"Various fires were set in the street and in garbage cans, a police car was spray-painted and vandalized, and there were attempts to set at least one business on fire," according to Portland Police. "Numerous projectiles were thrown at or launched at police and firefighters including rocks, bottles, ball bearings, fireworks, smoke bombs, and road flares."
The march through Portland's downtown was one of hundreds that took place in the U.S. and around the world Monday, as demonstrators urged more protections and benefits for workers. But after a paramedic was hit with a Pepsi can, other violence ensued and numerous fires were set, police say, leading officials to revoke the rally's permit.
Officers then faced the task of trying to apprehend suspects who were "running all over" downtown Portland, police say.
Police in Olympia, Wash., say they were confronted with a "mob" of masked and violent protesters who threw rocks and used slingshots to target officers. The situation settled down after officers used "crowd dispersal devices" and arrested several people.
Monday's rally in Portland got off to a peaceful start, OPB reports, saying families and children were among the hundreds of people who watched performances at a rally in Shemanski Park, the start and end point of the march.
But at the outer edges of the rally, police say, they confiscated "sticks, poles and homemade shields" from people as they arrived.
"Things are so screwed up in this country," rally attendee Martin Anderson told OPB. "You've got a city right here that's full of homeless people and you've got a president ... whose budget is going to cut 40 percent to the EPA and end Meals on Wheels. We don't like those kinds of things."
The station adds that another rally was held at the state Capitol in Salem, where hundreds of demonstrators spoke against plans to crack down on immigration to the U.S.