They were police officers attending to their lawful business for which they are (at least supposed to be) properly trained and equipped and constitutionally allocated to this very role.
The shooting of the officer was tragic but not unusual in a country where firearms are legal and gun crime epidemic.
However, this has nothing to do with this situation. I have made my view clear on ICE in my last post. But if they at least stuck to their purview of entry, search, seizure, arrest and removal linked exclusively to illegal immigration, I would have less to say. The problem of illegal immigration is a critical issue facing all Western countries (note - my posts are not "progressive" pro-migrant) but one that has to be addressed proportionately, in line with a rule of law that took centuries to embed, and be consistent with the conduct of a free and liberal democracy. That they have resorted to armed militia as a quick fix is more indicative of an incompetent government paying attention to political expedience over practical resolution. It represents a deep and worrying malaise in that country.
ICE have now exceeded their ill-defined power twice with lethal consequences. And given their hasty set up, vast power and resources and murky parameters, I fear this could be the beginning of a long list of balls-ups and a period of history the USA will look back to with a degree of shame like Prohibition, Jim Crow, McCarthy, Vietnam, Watergate etc.
The fact that even Trump has been forced to row back and remove elements of ICE from Minnesota must surely give you cause to pause and think that, perhaps, ICE may have screwed up.