Police officers detain a demonstrator during a protest against police violence and racial injustice in Portland, Oregon, US, August 24, 2020. (Reuters photo)

Police arrested 19 protesters in Portland, Oregon as anti-racism demonstrations flared there again overnight on Monday with officers using smoke grenades and pepper balls to control the crowds.

In a statement, the Police Department acknowledged that officers deployed some crowd control munitions, noting the arrestees were apprehended mostly on charges of disorderly conduct and interfering with officers.

Police also declared the demonstration as unlawful, later upgrading it to a riot after protesters set a fire in an apartment building.

Some 300 protesters, who gathered in the downtown area, marched to the apartment of Portland Mayor Ted Wheeler to demand his resignation.

Meanwhile, Acting Department of Homeland Security Secretary Chad Wolf called on Wheeler to request federal assistance, according to Fox News.

We are standing by to support Portland. At the same time, President Trump has made it abundantly clear that there will come a point when state and local officials fail to protect its citizens from violence, the federal government will have no choice but to protect our American citizens, Fox News said Tuesday, citing a letter it obtained from Wolf to Wheeler dated Aug. 31.

Nightly protests have been held in Portland since the police shooting death of George Floyd, a 46-year-old Black man, in Minneapolis on May 25.

Tactical officers had been sent to Portland but the federal government began withdrawing them in late July after discussions with Oregon Governor Kate Brown, who tweeted the federal officers acted as an occupying force & brought violence.

However, state police and officers from neighboring suburbs were sent to Portland on Monday to help local officers.

The fresh demonstrations took place in Oregon the night before President Donald Trump was due to visit Kenosha, Wisconsin, where police shooting of another black man triggered mass protests.

On August 23, a white police officer shot Jacob Blake, 29, in front of his children during an arrest.

Kenosha is in one of the most significant swing states of the electoral map. The US president said he would not meet the Blake family.

He also declined to condemn violent acts by his supporters who fired paint pellets and pepper spray during a confrontation with counter-protesters at the weekend in Portland.

SOURCE: PRESS TV