DAYS of demonstrations against immigration agents continued to leave Minnesota in a state of tension yesterday.

The day before, federal authorities used tear gas to break up crowds of whistle-blowing activists as state and local leaders sued to fight the enforcement surge that led to the fatal shooting of a Minneapolis woman.

Confrontations between federal agents and protesters continued throughout the day and across multiple cities on Monday. 

Agents fired tear gas in Minneapolis as a crowd gathered around immigration officers questioning a man.

Later that night, confrontations erupted between protesters and officers guarding the federal building being used as a base for the crackdown in Minneapolis and St Paul.

With the Department of Homeland Security pledging to send more than 2,000 immigration officers into Minnesota, the state, joined by the Twin Cities, sued the Trump administration on Monday to try to halt or limit the surge.

The lawsuit says the Department of Homeland Security is violating the first amendment and other constitutional protections. 

It accuses the Republican administration of President Donald Trump of violating free speech rights by focusing on a progressive state that favours Democrats and welcomes immigrants.

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

The Department of Homeland Security says it has made more than 2,000 arrests in the state since December.

The days after Ms Good was shot in the head by an Immigration and Customs Enforcement (ICE) officer while at the wheel of her SUV have seen dozens of protests or vigils held across the US to honour the mother of three and passionately criticise the Trump administration’s tactics.

In response to Monday’s lawsuit, Homeland Security spokeswoman Tricia McLaughlin accused Minnesota officials of ignoring public safety.

“President Trump’s job is to protect the American people and enforce the law — no matter who your mayor, governor or state attorney general is,” Ms McLaughlin said.

The Trump administration has repeatedly defended the immigration agent who shot Ms Good, claiming that she and her vehicle presented a threat.

But that explanation has been dismissed by Minnesota Governor Tim Walz, Minneapolis Mayor Jacob Frey and others, based on videos of the confrontation.

The government also faces a new lawsuit over a similar immigration crackdown in Illinois.

More than 4,300 people were arrested last year in Operation Midway Blitz as masked agents swept the Chicago area. 

The lawsuit by the city and state says the campaign had a chilling effect, making residents afraid to leave home.