An ICE agent has been charged with assault for allegedly pointing his gun at people in car while driving on a Minneapolis highway, prosecutors in Minnesota said on Thursday.

Hennepin county attorney Mary Moriarty said she believed it was the first criminal case brought against a federal immigration officer involved in the Trump administration’s crackdown on immigration enforcement that surged federal authorities into cities including Los Angeles, Chicago, Portland and New Orleans.

An arrest warrant says Gregory Donnell Morgan Jr was charged with two counts of second-degree aggravated assault. The warrant says Morgan was working as an Immigration and Customs Enforcement (ICE) officer in the Minneapolis area on 5 February when he pointed a gun at the occupants of a vehicle on Minnesota state highway 62.

Department of Homeland Security (DHS) and justice department officials didn’t immediately respond to emails seeking comment. The Associated Press called a number associated with Morgan and sent a message to his possible email address but did not receive any immediate response.

Moriarty said during a news conference that Morgan was driving a rented, unmarked SUV on the shoulder of the highway when a car on the road moved into the shoulder to try to slow Morgan down, not knowing he was a federal officer. After the car returned into the legal lane, Morgan pulled up alongside and pointed his service weapon at the people in the car.

Morgan, 35, and his partner, who was not charged, were on their way to the federal building to end their shift when they were caught in traffic. Charging documents note Morgan did not say the incident occurred during an enforcement action.

According to the charging documents, Morgan told a Minnesota state patrol officer that he pulled up alongside the victim’s vehicle, drew his firearm and yelled “Police Stop.” The warrant says the victims couldn’t hear him because their windows were up.

Morgan was charged with two counts of assault because he threatened both people in the vehicle, and there is a warrant out for his arrest, Moriarty said.

She said Morgan’s actions were beyond the scope of a federal officers’ authority.

“There is no such thing as absolute immunity for federal agents who violate the law in the state of Minnesota,” she said.

In Minnesota, felony second-degree assault is punishable by up to seven years in prison, or up to 10 years imprisonment if the assault inflicted “substantial bodily harm”.