A man arrested for impersonating a police officer during an anti-ICE protest in Chicago had a loaded semi-automatic weapon, badges and fake documents, police sources said.

Tens of thousands of protesters are expected to gather in downtown Chicago and across the country Saturday in opposition to President Donald Trump’s administration. Organizers say the national No Kings Day of Defiance aims to reject authoritarianism,

The woman was taken to Northwestern Memorial Hospital where she was treated and released, Chicago police said.

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

Follow along for live updates as thousands of people nationwide have shown up at protests and rallies opposing ICE raids.

The Chicago Loop is expected to see its third large-scale protest this week against ICE raids and the Trump administration. It comes as ICE tactical teams are supposedly set to begin work in the city,

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

PHOTOS: Take a peek at life in the city through the eyes and lenses of the Block Club Chicago staff.