Chicago police clashed with members of a local Antifa group outside a Cook County courthouse Tuesday evening. Three protesters were detained.

The violent Antifa activists gathered outside the Cook County courthouse at Belmont and Western starting around 2 PM, claiming to protest a hearing of a man they say is a “white supremacist,” DNA Info reported.

Police approached the protesters and asked them to stop blocking the streets and to move their marching to a sidewalk, but as the discussion continued, at least one protester began to scuffle with officers.

In seconds, several protesters jumped in and began a brawl with police.

Breaking: Scuffle ensues between antifa and police outside North Center courthouse pic.twitter.com/puGTNG91Cm — Tony Briscoe (@_TonyBriscoe) August 15, 2017

The group consisted of perhaps a dozen protesters, some of them wearing black masks. In a video of the incident, one protester with a red bandana over his face is seen beating on the car of a passerby.

Other demonstrators were also seen screaming at vehicles as they drove by the scene.

Chicago police reported that three protesters were detained. Officials also could not confirm that anyone appearing in court that day was connected to any white supremacist group.

Follow Warner Todd Huston on Twitter @warnerthuston.