A protest group has threatened that "nothing moves on Wednesday" if the Portland police chief is not fired following Friday's inauguration protest in downtown Portland.

Jacob Bureros of Direct Action Alliance issued an open letter to Mayor Ted Wheeler on Monday, claiming the Portland Police Bureau and the city of Portland, "knowingly and intentionally set out to incite violence on the streets of Portland."

Police said pepper spray and tear gas was used after rocks, bottles, flares and unknown liquids were thrown at officers during the protest march. Police also said some protesters were armed with sticks and clubs.

The rally began at 3 p.m. Friday with flags set on fire at Pioneer Courthouse Square and concluded by 9:30 p.m. as protesters dispersed downtown.

Four people were arrested and another person was cited on second-degree disorderly conduct charges.

As the night went on, the Portland Police Bureau stated on Twitter that the protest had become an "unlawful assembly" and later stated, "This is no longer a peaceful protest."

Due to rocks, bottles, flares, unknown liquid being thrown at ofcs, this is no longer a peaceful protest. Crowd told repeatedly to disperse.— Portland Police (@PortlandPolice) January 21, 2017

Protesters were blocked by officers from crossing Portland bridges. Bureros, in his letter to Wheeler, stated, "They attacked us first on the Burnside Bridge then they deliberately corralled us into Pioneer courthouse square where they gassed us - men, women, children, everyone - they hit us with concussion grenades, rubber bullets and batons."

Different approach by police tonight. Blocking streets and bridges ahead of marchers. #fox12oregon#JAN20PDX pic.twitter.com/JxHIuN6CPq— Simon Gutierrez (@sggutierrez) January 21, 2017

Following Friday's protest, organizers Portland's Resistance posted on Facebook: "Portland, we need you to demand explanations for police violence."

"The night was wonderful until the peacefully assembling protestors were attacked and denied their First Amendment rights by our city's police department. This is a disgusting abuse of power," according to Portland's Resistance.

Bureros, in demanding the firing of Police Chief Mike Marshman by Tuesday, concluded, "You only rule by our consent, we are about to stop consenting."

Wheeler and Marshman stated before the protest that marchers would not be allowed on highways and would be stopped from blocking public transportation.

Wheeler said Monday that by the measures of limited acts of vandalism, minimal disruptions to transit and no serious injuries, the weekend was "highly successful."

"No one likes to see the use of crowd control devices. I certainly don't. When these devices are used, I want to be sure that they are used under the proper circumstances. Early indications are that their use on Friday night was appropriate. I will of course review post-action reports to make sure that was the case," Wheeler said in a statement about the protests Monday.

An estimated 100,000 people attended the Women's March of Portland on Saturday. No arrests were made during that event and the Portland Police Bureau posted numerous photos online of officers posing with marchers Saturday.

Even the pups had a good time today at #womensmarchpdx. pic.twitter.com/rzkQj4Co2q— Portland Police (@PortlandPolice) January 21, 2017

Anyone who attended the protests and wants to file a complaint or a commendation relating to sworn officers of the Portland Police Bureau can contact the city's

Independent Police Review Division

.

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