WASHINGTON, July 20 — US President Donald Trump condemned protests in Portland, Oregon, and violence in "Democrat-run” cities yesterday as his Republican administration prepared to intervene in urban centres he says have lost control of anti-racism demonstrations.

Federal law enforcement officers, armed with a new executive order aimed at protecting US monuments, last week started cracking down on crowds gathering in Portland to protest police brutality and systemic racism.

Facing declining polling numbers before his November 3 election against Democrat Joe Biden, Trump is making "law and order” a central campaign issue to appeal to critical suburban voters.

The crackdown in the liberal bastion of Portland drew widespread criticism and legal challenges as videos surfaced of camouflage-clad officers without clear identification badges using force and unmarked vehicles to arrest protesters without explanation.

Oregon's governor and Portland's mayor, both Democrats, called the move an abuse of power by the federal government and the state filed a lawsuit against the US agencies involved.

Trump did not back down yesterday.

"We are trying to help Portland, not hurt it. Their leadership has, for months, lost control of the anarchists and agitators. They are missing in action. We must protect Federal property, AND OUR PEOPLE,” Trump wrote in a Twitter post.

Nationwide crackdown

White House Chief of Staff Mark Meadows said Attorney General William Barr and Acting Homeland Security Secretary Chad Wolf are working on measures the administration can take to counter the unrest.

"You'll see something rolled out this week as we start to go in and make sure that the communities, whether it's Chicago or Portland, or Milwaukee, or someplace across the heartland of the country, we need to make sure our communities are safe,” Meadows said on Sunday Morning Futures.

The announcement is expected to expand a new Justice Department initiative that sends federal law enforcement into cities facing protests.

Portland Mayor Ted Wheeler said yesterday the federal authorities were sharply escalating the situation.

"Their presence here is actually leading to more violence and more vandalism,” Wheeler said on CNN's State of the Union programme. "And it's not helping the situation at all. They're not wanted here. We haven't asked them here. In fact, we want them to leave.”

In an interview on Fox News Sunday, Trump attributed the increase in violence in cities such as Chicago and New York by saying "they’re Democrat-run cities, they are liberally run. They are stupidly run.”

The Republican president last month threatened to send US military troops to quell protests that erupted over police brutality and racism after the killing of a Black man, George Floyd, by a Minneapolis police officer.

Oregon's attorney general, Ellen Rosenblum, on Friday filed a federal lawsuit against the Department of Homeland Security (DHS), the US Marshals Service, and Customs and Border Protection (CBP), saying they had violated peoples' civil rights by seizing and detaining them without probable cause.

The American Civil Liberties Union is calling the situation in Portland a "constitutional crisis.” It filed a lawsuit on Friday against DHS and the US Marshals Service and promised more suits in the coming days.

A CBP spokeswoman said last week that agents had been deployed to Portland to support a newly launched DHS unit charged with enforcing last month's executive order from Trump to protect federal monuments and buildings.

The state's lawsuit included a sworn declaration from resident Mark Pettibone, who in prior media interviews said he had been unlawfully detained by federal police after he was leaving a peaceful protest in downtown Portland.

"Without warning, men in green military fatigues and adorned with generic 'police' patches, jumped out of an unmarked minivan and approached me,” he wrote of the incident on July 15.

"I did not know whether the men were police or far-right extremists, who, in my experience, frequently don military-like outfits and harass left-leaning protesters in Portland. My first thought was to run. I made it about a half-block before I realised there would be no escape from them.” — Reuters