The message, dated Thursday, was prepared by the agency for Chad F. Wolf, the acting secretary of Homeland Security, as he arrived in Portland to view the scene in person, according to a copy of the memo obtained by The New York Times. It listed federal buildings in the city and issues officers faced in protecting them.

The memo, seemingly anticipating future encounters with protesters in other cities as the department follows President Donald Trump’s guidance to crack down on unrest, warns: “Moving forward, if this type of response is going to be the norm, specialized training and standardized equipment should be deployed to responding agencies.”

The tactical agents deployed by Homeland Security include officials from a group known as BORTAC, the Border Patrol’s equivalent of a SWAT team, a highly trained group that normally is tasked with investigating drug smuggling organizations, as opposed to protesters in cities.

The Department of Homeland Security did not immediately respond to a request for comment.

The issue is playing out as the aggressive federal campaign to suppress protests in Portland appears to have instead rejuvenated the city’s movement, as protesters gathered by the hundreds late Friday and into Saturday morning — the largest crowd in weeks.

Federal officers at times flooded street corridors with tear gas and shot projectiles from paintball guns, while demonstrators responded by shouting that the officers in fatigues were “terrorists” and chanting: “Whose streets? Our streets.”

A court ruling has largely prohibited the local police from using tear gas during the recent protests, which have played out for more than 50 consecutive nights.

With one Portland protester severely injured in front of the federal courthouse and others pulled by unidentified federal agents into unmarked vans, the extraordinary campaign to subdue protesters has led to widespread condemnation of the federal response in Portland and beyond.

While the protesters have repeatedly decried the city’s own police tactics, Mayor Ted Wheeler, who also serves as police commissioner, and other leaders have united in calls for federal agencies to stay away. Jo Ann Hardesty, a city commissioner, went to join protesters gathered outside the county Justice Center downtown, saying the city would “not allow armed military forces to attack our people.”

“Today we show the country and the world that the city of Portland, even as much as we fight among ourselves, will come together to stand up for our Constitutional rights,” Hardesty said Friday.

While officials from the U.S. Department of Homeland Security have described the stepped-up involvement of federal officers as part of an effort to oppose lawlessness in the city, state and local leaders contended that the federal officers themselves may be violating the law.

Prosecutors have opened a criminal investigation into the injury of one protester, who appeared to have been shot in the head with a less-lethal weapon outside the federal courthouse in downtown Portland. Ellen Rosenblum, the state’s attorney general, has filed a lawsuit, accusing federal officers of unlawful tactics in how they went about detaining people by pulling them into unmarked vans.

The pushback against the militarized federal deployment involving officers in fatigues and tactical gear has also extended to the streets, where the presence of those federal agents has rejuvenated a movement that had shown signs of finally slowing down after weeks of protest against police violence and militarization.

Hundreds continued to demonstrate after midnight Saturday, playing music, holding shields, tearing down temporary fences and throwing fireworks at the county’s Justice Center.

Along with street medics, protesters also have the support of a snack van that offers free Gatorade and instant noodles, and a makeshift kitchen called Riot Ribs that cooks bratwursts and Beyond Meat sausage. Someone on Saturday had set up a stand selling T-shirts promoting racial equity and hand washing.

The protests have long featured a mix of tactics, with some there displaying signs to sustain a Black Lives Matter movement that emerged in the aftermath of George Floyd’s death in May. Others have engaged in more unruly responses, such as graffiti or throwing objects at officers. Dozens have been arrested over the weeks, including some by federal officers, such as a man accused of hitting an officer with a hammer last week.

Protests around the federal courthouse — tagged with messages such as “Stop Using Violence On Us” and “History Has Its Eye On You” — have drawn the ire of federal leaders. Wolf got a tour there this week and shared images of himself in front of graffitied walls.

The arrival of a more aggressive federal presence came after Trump, who at one point called on states to “dominate” protesters, directed federal agencies to increase their presence to protect federal properties, including statues and monuments that have at times been the target of protesters. Trump said last week that he had sent personnel to Portland because “the locals couldn’t handle it.”

Gov. Kate Brown of Oregon said in an interview that she believed that the protests were starting to ease before the federal officers waded into the scene. She said she had asked Wolf to keep federal agents off the streets but that he rejected the suggestion.

Wheeler, the mayor, said he got the same response. But he said he believed the unified local response could change the federal tactics and keep federal officers off the streets.

“I can’t recall a single instance where we have had federal, state and local officials all in alignment, saying the presence of federal troops in our city is harmful to our residents,” Wheeler said.

Wheeler himself has been the target of protests, with crowds at times gathering outside of his condo. For weeks, he has called for an end to destructive demonstrations, saying he was concerned about “groups who continue to perpetrate violence and vandalism on our streets.”

Sen. Jeff Merkley, D-Ore., said in a tweet that he and Oregon’s other Democratic senator, Ron Wyden, next week would introduce an amendment to the defense bill to stop the Trump administration “from sending its paramilitary squads” onto America’s streets.

Rosenblum said her office was working with the Multnomah County district attorney, Rod Underhill, on a criminal investigation focused on the injury of a protester on July 12. In that case, video appeared to show a man being struck in the head by an impact munition near the federal courthouse, and his family said he subsequently needed surgery.

The attorney general’s office also filed a lawsuit late Friday accusing federal officers of using unlawful tactics. Protesters, along with videos posted on social media, have described scenes of federal officers seizing people and pulling them into unmarked vans.

The American Civil Liberties Union Foundation of Oregon has also filed in court to curtail the actions of federal officers, and the group said “many” more lawsuits would be forthcoming.

Mary B. McCord, a professor at Georgetown Law and former national security official at the U.S. Department of Justice, said the federal tactics and use of unmarked vehicles were reminiscent of the much-criticized federal response to demonstrations in Washington in June.

McCord said federal officials were on dangerous ground with the tactics they were using, including seizing and detaining protesters off the streets and seemingly portraying all protesters as part of a dangerous movement.

“It sends the message that these people are terrorists and need to be treated like terrorists,” McCord said.

She added: “This is the kind of thing we see in authoritarian regimes.”

This article originally appeared in The New York Times.

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