The U.S. Justice Department has opened a criminal investigation into Minnesota officials, including Governor Tim Walz and Minneapolis Mayor Jacob Frey, over allegations that they conspired to obstruct federal immigration enforcement, according to a source familiar with the matter. 

The source, who spoke on the condition of anonymity, said that subpoenas have been prepared for both Governor Walz and Mayor Frey as part of the investigation. However, it was not immediately known whether those subpoenas had been formally served. The investigation was first reported by CBS News. 

According to the source, the inquiry is based on public statements made by Walz and Frey concerning the deployment of thousands of Immigration and Customs Enforcement (ICE) officers and U.S. Border Patrol agents to the Minneapolis region. These federal agents were sent under orders from President Donald Trump in recent weeks as part of an intensified immigration enforcement effort. 

Reacting to the news of the investigation, Governor Walz criticised the move and accused the federal government of misusing its power. In a post on social media, Walz said the justice system was being used to threaten people seen as political opponents of President Trump. “Two days ago it was Elissa Slotkin. Last week it was Jerome Powell. Before that, Mark Kelly. Weaponising the justice system against your opponents is an authoritarian tactic,” Walz wrote. 

Walz was referring to U.S. Senators Elissa Slotkin of Michigan and Mark Kelly of Arizona, both Democrats, who recently released a video urging members of the U.S. military to resist illegal orders. He also mentioned Federal Reserve Chairman Jerome Powell, who has been repeatedly criticised by Trump for being too slow to raise interest rates. 

Minneapolis Mayor Jacob Frey also responded strongly after CNN reported on the investigation. In a separate statement, Frey said, “This is an obvious attempt to intimidate me for standing up for Minneapolis, local law enforcement, and residents against the chaos and danger this Administration has brought to our city.” 

The Justice Department declined to comment on the investigation. However, U.S. Attorney General Pam Bondi addressed the issue on social media platform X. In her post, Bondi wrote, “A reminder to all those in Minnesota; No one is above the law.” 

Legal experts have noted that it would be highly unusual for federal prosecutors to pursue a criminal conspiracy case based solely on statements made by public officials about government policies. 

The Trump administration has deployed nearly 3,000 federal agents to Minnesota since early last week. This sudden increase in immigration enforcement has led to widespread anger and protests in Minneapolis, the state’s largest city. Demonstrators have taken to the streets to oppose the presence of heavily armed federal officers and what they describe as a militarised approach to immigration enforcement. 

Tensions escalated further after an ICE agent fatally shot a U.S. citizen, Renee Good, 37, on January 7. Good was shot while sitting behind the wheel of her car in Minneapolis. The shooting sparked daily protests that later spread to other cities across the region. Confrontations between residents and federal officers have since become increasingly tense. 

Governor Walz has urged protesters to remain peaceful but has also encouraged residents to document interactions with ICE agents. He asked citizens to record videos of arrests or other encounters involving federal officers and members of the public. Walz said such recordings could help create a database for potential “future prosecution” of wrongdoing by law enforcement. 

Both Walz and Frey have repeatedly called on President Trump to end the ICE deployment. They have described the operation as reckless and dangerous, saying it is designed to create fear, chaos, and media attention rather than ensure public safety. The officials have warned that the presence of large numbers of federal agents is putting civilians at risk. 

Earlier this week, Deputy U.S. Attorney General Todd Blanche blamed Walz and Frey for the confrontations in Minneapolis. Blanche said he was focused on stopping the situation by “whatever means necessary.”