Tensions escalated outside a federal building in Minneapolis on Monday as federal agents deployed tear gas and rubber bullets to disperse protesters opposing immigration enforcement activities in the Twin Cities.

The confrontation took place at the Bishop Henry Whipple Federal Building, which accommodates various federal entities, including U.S. Immigration and Customs Enforcement, the Department of Homeland Security, and the Department of Veterans Affairs.

The standoff began when demonstrators reportedly threw snowballs at federal vehicles, prompting a response from authorities.

An image captured the scene as a firework exploded near the fencing outside the federal building during the protests on January 12, 2026, in Minneapolis. (AP Photo/Jen Golbeck)

Following warnings from the agents, they resorted to crowd-control measures, deploying chemicals to disperse the group of approximately 80 to 90 protesters. The situation prompted many demonstrators to retreat as agents fired rubber bullets and released tear gas.

One protester threw a firework over a fence while fleeing, and it exploded shortly afterward. Other protesters were also seen launching fireworks toward agents, with the munitions lighting up the night sky. 

Officers and agents maintained a perimeter around the building late Monday, and it was unclear whether any arrests had been made.

The unrest came as Minnesota, joined by the cities of Minneapolis and St. Paul, filed a lawsuit Monday seeking to halt or limit a surge of federal immigration enforcement in the Twin Cities.

WATCH: Anti-ICE agitators harass federal agents in Minneapolis 

“This is, in essence, a federal invasion of the Twin Cities in Minnesota, and it must stop,” state Attorney General Keith Ellison said at a news conference.

The lawsuit alleges the Department of Homeland Security violated the First Amendment and other constitutional protections, accusing the Trump administration of targeting a progressive, Democratic-leaning state that welcomes immigrants. The suit claims the federal operation has flooded the Twin Cities with armed agents, sparked fear and unrest, and interfered with state and local authorities.

Fireworks are set off by protesters outside the Bishop Henry Whipple Federal Building on Monday, Jan. 12, 2026, in Minneapolis. (AP Photo/Jen Golbeck)

According to court filings, the plaintiffs accuse federal immigration agents of carrying out militarized raids across the Twin Cities, including stops at schools and hospitals, engaging in racial profiling, warrantless arrests and excessive force, and overwhelming local law enforcement. The lawsuit claims the enforcement surge was politically motivated retaliation rather than legitimate immigration enforcement.

The legal action comes nearly a week after an ICE agent shot and killed a 37-year-old Minneapolis woman during a federal enforcement operation in south Minneapolis. Federal officials said agents were attempting to make arrests when the woman tried to use her vehicle as a weapon against officers, prompting an agent to fire in self-defense.

Fireworks are set off by protesters outside the Bishop Henry Whipple Federal Building on Monday, Jan. 12, 2026, in Minneapolis.

The Department of Homeland Security said more than 2,000 arrests have been made in Minnesota since December as part of what ICE has described as its largest enforcement operation in the state.

ICE officials on Saturday released a shocking list of the “worst of the worst” criminal illegal immigrants arrested during their recent surge. ICE officials said those arrested during the surge included convicted murderers, child rapists, pedophiles, domestic abusers and other violent offenders.