US President Donald Trump has warned Minneapolis Mayor Jacob Frey he is "playing with fire" after the Democratic leader reiterated his city would not help federal agents enforce immigration law.
Just a day earlier the president said his administration would "de-escalate a bit" in the city.
Amid the mixed signals from the White House, tensions remained high in Minneapolis, where observers and activists say immigration raids had not slacked but appeared to be more targeted.
The city has been convulsed by unrest, including confrontations between protesters and immigration agents, after two US citizens were shot dead by federal agents, including Saturday's killing of nurse Alex Pretti.
US Attorney General Pam Bondi said on social media federal agents had arrested 16 people in Minnesota for allegedly assaulting, resisting or impeding federal law enforcement, and lawlessness would not be tolerated.
Trump's administration had indicated it will soften its approach, dispatching border tsar Tom Homan to take over the operation from Gregory Bovino, the Border Patrol official whose aggressive tactics drew widespread criticism.
The two border officers who shot at Pretti have been placed on administrative leave, according to an agency spokesperson, who added it was "standard protocol".
A senior administration official said Homan's arrival would mark a shift to more traditional targeted operations rather than the broad street sweeps Bovino has led in multiple cities.
Observers and activists told Reuters that Immigration and Customs Enforcement activity appeared to slow somewhat on Tuesday, US time, before resuming in full on Wednesday.
"They definitely shift around," said Patty O'Keefe, a community ICE observer in south Minneapolis. "Let up for a few days so people let their guard down, I think."
Under mounting political pressure, Trump had dialled back his attacks on Frey and Governor Tim Walz after speaking with both Democrats in the wake of Pretti's killing, vowing to work with them to lower the temperature.
But on social media on Wednesday, Trump faulted Frey for saying the city would not enforce immigration laws.
"Could somebody in his inner sanctum please explain that this statement is a very serious violation of the Law, and that he is PLAYING WITH FIRE!"
In response, Frey wrote on social media: "The job of our police is to keep people safe, not enforce fed immigration laws."
In another sign political tensions remain heated, US Representative Ilhan Omar, a Minneapolis Democrat and a frequent Trump target, was sprayed with an unknown liquid by a man with a syringe during a Tuesday town hall, where she called for the abolition of ICE.
Omar was unharmed. Minneapolis police arrested the suspect, Anthony Kazmierczak, 55, for third-degree assault.
The FBI is investigating the attack, and authorities believe the substance was non-lethal and non-chemical, a Justice Department official said.
Pretti, 37, was shot dead during protests near his home on Saturday, and some administration officials immediately accused him of planning to kill officers, citing the handgun he was carrying.
But video verified by Reuters showed Pretti held only a phone in his hand when Border Patrol agents pushed him to the ground.
Video also showed an agent found Pretti's gun near his waist and removed it seconds before another agent shot a restrained Pretti in the back.
