(PORTLAND, Ore.) -- "Numerous" people have been arrested in a May Day march in downtown Portland, Oregon, after protesters threw bottles and other items at police officers monitoring the event, authorities said.
The Portland Police Bureau said that lead balls, smoke bombs, paint, glass bottles and full cans of Pepsi were "launched" at police. Officers were forced to put on protective helmets and other protective equipment due to the items that were being thrown at them, police said.
A window was also broken at the Edith Green-Wendell Wyatt Federal Building, police said.
Police initially encouraged peaceful protesters to separate themselves from "anarchists committing acts of violence/property damage." Authorities also advised that families with children at the march to "immediately leave" due to the mounting violence.
Anarchists committing acts of violence/property damage during #MayDayPDX march. Permitted group encouraged to separate from them.— Portland Police (@PortlandPolice) May 1, 2017
Just before 4:30 p.m., police said the permit for the march had been canceled and informed everyone in the vicinity to "leave the streets" due to the "unsafe conditions."
Permit is now cancelled - everyone in march should leave the streets. Unsafe conditions for lawful participants & families. #MayDayPDX— Portland Police (@PortlandPolice) May 1, 2017
After announcing that the permit had been canceled, Portland police asked law-abiding participants to use the sidewalks and leave the area, adding that anyone remaining in the street would be subject to arrest.
Anyone in area of SW 3rd Avenue and Morrison is subject to arrest. Everyone ordered to clear the area or be subject to arrest. #MayDayPDX— Portland Police (@PortlandPolice) May 1, 2017
Police said "impact munitions" and "chemical munitions" were deployed on the crowds due to the "numerous projectiles being thrown at police."
Protesters then began to start fires and throw "incendiary devices" at officers, including fireworks, smoke bombs and Molotov cocktails, police said. One police car was destroyed by protesters.
May Day, which falls on the first day of May, is also known as International Workers' Day, which has long been an occasion for political action by labor unions and other progressive organizations.
Demonstrations were planned on Monday in major cities including New York Seattle, San Francisco and Los Angeles.
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