Officers spotted the man with "police identifiers" leaving a parking garage around 5 p.m. in the 200 block of South Michigan Avenue, Chicago police said.

Chicago is an anchor city for the "No Kings" protests Saturday, and city officials said they are prepared for the crowds expected.

The "No Kings" Chicago protest Saturday is one of the anchor events for a national anti-Trump movement. Over 1,000 rallies will be held the same day Trump holds a military parade in the capital for his birthday.

The Chicago No Kings rally comes as protests have ramped up against ICE and the Trump administration this week locally and in Los Angeles, where the National Guard and Marines have been deployed against the wishes of local leaders.

At 4 p.m. as protesters were gathering, a counterprotester came to the scene — prompting angry chants to erupt from the main protest.

Thousands of protesters marched in Chicago against Immigration and Customs Enforcement raids in their city and President Trump’s deployment of troops in Los Angeles.

RIPPLE EFFECT: Thousands of demonstrators marched through downtown Chicago on Tuesday, stopping traffic in the Loop and along DuSable Lake Shore Drive to protest the Trump administration’s immigration raids that have erupted in California and across the country.