As temperatures plummet in Minnesota, the struggle between the Trump administration and opponents of Operation Metro surge are playing out indoors: A judge has ruled federal agents can’t retaliate against peaceful protesters or stop people in their cars if they aren’t obstructing operations.

And in Washington, the Justice Department has launched an investigation into Minnesota Gov. Tim Walz and Minneapolis Mayor Jacob Frey for possible obstruction of federal law enforcement, sources familiar with the matter told CNN.

Walz did not confirm the investigation to CNN but accused the federal government of “weaponizing the justice system and threatening political opponents,” while Frey said he “will not be intimidated.” The Justice Department has not commented.

Outside on the streets, heated clashes have slowed to a simmer as plunging temperatures and fierce winds of 30 to 40 mph blast through the Twin Cities. The wind chill is dipping below zero degrees and it’s expected to stay that way until the middle of next week.

From Saturday night into Sunday morning, the actual air temperature will drop below zero, with blustery winds ushering wind chills as low as -20.

State and local leaders have urged the community to remain calm amid unrest that escalated earlier this week after a federal agent shot and wounded a Venezuelan national who federal officials said began to resist arrest and “violently assault” one of its officers, just a week after Renee Good was shot and killed by an ICE agent.

The Department of Homeland Security continues its presence in the city, saying 12 people were arrested in Minneapolis Thursday night.

“Last night in Minneapolis 12 anti-ICE agitators were arrested for assaulting law enforcement,” DHS posted on X Friday morning. “Reminder: it is a federal crime and a FELONY if you lay a finger on law enforcement or destroy federal property.”

Protesters were seen at the Bishop Henry Whipple Federal Building Friday — a day after federal officers in tactical gear deployed tear gas and percussion grenades to try to disperse crowds near the building Thursday.

Protests are expected to continue throughout the weekend despite frigid temperatures.

“Minnesotans are being racially profiled on a mass level,” said Rep. Betty McCollum, a Minnesota Democrat. “They are being kidnapped from our communities. Parents are seized in front of their children by masked federal agents.”