US cities including Portland have been rocked by protests against racial injustice sparked by the death of George Floyd in police custody in Minneapolis on May 25.

Federal officers use chemical irritants and projectiles to disperse Black Lives Matter protesters in Portland, Oregon, July 24, 2020.
Federal officers use chemical irritants and projectiles to disperse Black Lives Matter protesters in Portland, Oregon, July 24, 2020. (AP)

US police and security forces must not use disproportionate force against protesters and journalists in US cities including Portland or detain them unlawfully, the United Nations human rights office has said.

Responding to questions about violent clashes in the US city of Portland between federal forces and demonstrators protesting against racism and police brutality, a UN spokeswoman stressed that the right to peacefully assemble and protest must be protected.

"Peaceful demonstrations that have been taking place in cities in the US, such as Portland, really must be able to continue," UN rights office spokeswoman Elizabeth Throssel told reporters in Geneva on Friday.

People must be able to demonstrate, and journalists must be able to cover such protests, without "risking arbitrary arrest or detention, being subject to unnecessary disproportionate or discriminatory use of force or suffering other violations of their rights," she said.

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Disproportionate use of force

Protests raged in the US after the killing of George Floyd, an African American man who died at the hands of police in Minneapolis on May 25.

Those protests began losing steam earlier this month, before reports emerged of federal officers snatching Portland protesters and taking them away in unmarked vehicles, spurring a fresh wave of demonstrations.

Throssel said that the reports of unidentified officers making arrests were a particular cause for concern.

She noted that such practices could "give rise to arbitrary detention and other human rights violations.

"We would stress ... that the authorities should ensure that the federal and local security forces deployed are properly and clearly identified and use force only when necessary, proportionate, and in accordance with international standards," she said.

Victims, she said, should have the right to a remedy and be able to seek an investigation of any rights violations.

Globally, she added, authorities must ensure that people deployed for law enforcement do not threaten the "use of force to deter peaceful protesters."

Trump's controversial decision

In a controversial move, President Donald Trump has dispatched federal agents to cities like Portland amid unrest on the sidelines of protests seeking racial justice in the wake of the George Floyd killing by police in May.

Unrest has escalated in Portland after some federal agents were accused of whisking people away in unmarked cars without probable cause.

The US Justice Department said on Thursday it would investigate the use of force by federal agents against protesters in Portland after another night of unrest in which Mayor Ted Wheeler was teargassed.

The investigations follow public anger over the deployment of federal border patrol officers to Portland against the wishes of local officials, and President Donald Trump's administration has said it is sending a similar contingent to Seattle.

READ MORE: Chaotic Scenes in Portland as Backlash to Federal Deployment Grows

Source: TRTWorld and agencies