US Attorney General William Barr, who faced intense scrutiny from Democrats on Tuesday over federal agents' presence and use of force against Black Lives Matter demonstrators in Portland, announced roughly 100 officers will be deployed across three other cities with Democrat mayors.
The attorney general justified the deployment of heavily armed and armoured officers amid a "disturbing increases in violent crime" in those areas, though violent crime overall throughout the US has been on a downward trend.
Operation Legend launched last month as a "sustained, systematic and coordinated law enforcement initiative in which federal law enforcement agencies work in conjunction with state and local law enforcement officials to fight violent crime," according to the Justice Department.
The presence of Department of Homeland Security officers in Portland, however, was established through an executive order aimed at protecting federal properties. On Wednesday, Oregon Governor Kate Brown announced that all Customs and Border Protection and Immigration and Customs Enforcement officers will be leaving downtown Portland starting on Thursday.
Its latest expansion would send most of the agents into Detroit, where 42 members of the FBI, Drug Enforcement Administration and Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) will work with the city's police department, while another 10 Detroit-based ATF agents will be reassigned to work gun crimes.
Cleveland and Milwaukee will each be sent "more than 25" agents from the FBI, DEA, ATF and US Marshals.
Michigan, Ohio and Wisconsin also are swing states, crucial electoral battlegrounds in which the president's presumed Democratic presidential rival Joe Biden has polled favourably in recent weeks while the president has faced declining poll numbers less than 100 days ahead of the election.
A group of Democratic mayors from across the US have urged the Trump administration to halt the deployment of militarised federal law enforcement in their cities following reports that officers had used violence force, shot tear gas, pepper spray and other potentially deadly projectiles at peaceful demonstrators. Protesters also reported that unidentified officers had indiscriminately arrested people on Portland's streets and placed them into unmarked vans.
The announcement appeared to have caught some local officials by surprise, though local law enforcement has insisted that the surge in federal agents will not be responding to protests.
Detroit Mayor Mike Duggan said the surge "was not initiated by the City of Detroit".
"So long as they are used in the continuing effort to enforce federal laws on illegal gun trafficking and gang violence, [Detroit Police Department] will continue its strong partnership with those agencies," he said.
He added that there is "no lawful basis for Homeland Security intervention in the Detroit protests today, or for any increased presence of Homeland Security agents in our community".
"Today's announcement appears to respect that position," he said. "We have to address the unacceptable level of gun violence in Detroit through greater efforts by federal, state, county, DPD, and community partners all working together. We hope today's announcement will prove to be an important step in that direction."
In a statement last week, Milwaukee Governor Tom Barrett said he was "extremely concerned that President Trump is looking for opportunities to create more political division in cities across the nation" following unrest in Portland.
"Federal agents are not welcome here for that purpose," he said. "If the federal presence is to truly cooperate with local law enforcement, then it is imperative the limits of their activities are clearly delineated and monitored."
Mr Trump has painted an apocalyptic portrait of American cities and lashed out at the "radical" mayors that govern them, while his administration has distinguished the work of Operation Legend from its presence at demonstrations in Portland and Seattle.
The latest round of deployments also includes nearly $30 million in federal funds to hire local police and other officers in the areas.
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