A federal judge on Saturday (Oct 4) temporarily blocked US President Donald Trump from deploying 200 Oregon National Guard troops to the city of Portland while a lawsuit challenging the move plays out.

The ruling by US District Judge Karin Immergut in Portland is a setback for Trump, a Republican, as he seeks to dispatch the military to cities he describes as lawless over the objections of their Democratic leaders.

Democratic Oregon Attorney General Dan Rayfield’s office filed the lawsuit on Sep 28, a day after Trump said he would send troops to Portland to protect federal immigration facilities from “domestic terrorists.”

The case was initially assigned to US District Judge Michael Simon, an appointee of Democratic President Barack Obama. He recused himself after the Trump administration raised concerns about comments made by his wife, a congresswoman, criticising the troop deployment. The case was reassigned to Immergut, who was appointed by Trump during his first term in office.

Oregon asked the court to declare the deployment illegal and block it from going forward, saying Trump was exaggerating the threat of protests against his immigration policies to justify illegally seizing control of state National Guard units.

While Trump described the city as "war ravaged", Oregon said that Portland protests were "small and sedate", resulting in only 25 arrests in mid-June and no arrests in the three-and-a-half-months since Jun 19. Oregon's lawsuit said that Trump announced the troop deployment after Fox News showed video clips from "substantially larger and more turbulent protests" in Portland in 2020.

The stark divide in how the two sides described the situation on the ground in Portland was evident at a Friday court hearing before Immergut.

US Department of Justice attorney Eric Hamilton said that "vicious and cruel radicals" had laid siege to the Portland headquarters of US Immigration and Customs Enforcement. The decision to send 200 troops - just 5 per cent of the number recently sent to respond to Los Angeles protests - showed restraint, Hamilton said.

Caroline Turco, representing Portland, said that there had been no violence against ICE officers for months and that recent ICE protests were "sedate" in the week before Trump declared the city to be a war zone, sometimes featuring less than a dozen protesters.

"The president's perception of what is happening in Portland is not the reality on the ground," Turco said. "The president's percepti...