CHICAGO (CBS) — A man involved with the “Occupy Chicago” movement has been charged with child pornography.

Robert Reitz, 21, of the 2000 block of South Canalport Avenue, was arrested Monday in the 100 block of West Quincy Street for an active warrant for aggravated child pornography, police said. He is being held without bond, according to the Cook County Sheriff’s office.

READ MORE: Chicago Weather: Rain Tapers Saturday Night, But More Scattered Showers Sunday

At the time of his arrest Reitz said he was involved with security for Occupy Chicago–a claim that was denied by protest organizers.

Reitz was arrested after officers smelled burnt cannabis and approached to investigate. Officers did a name check and learned he was wanted for a probation violation by the sheriff’s police.

READ MORE: At Least 16 People Shot, 1 Killed In Gun Violence In Chicago This Weekend

In a statement Wednesday morning, Occupy Chicago said, “We are an open movement, without a vetting system for our participants. Our community is based on trust. It is to be expected that the problems of society at large are sometimes present in our movement.

“Robert Reitz was a participant in our movement. He did spend time at our headquarters. He is not a member of our Safety and Peacekeeping Committee.”

The statement added that Reitz “is no longer welcome in the Occupy Chicago community.”

MORE NEWS: At Bond Hearing For Man Authorities Say Was With Him, Prosecutors Say 13-Year-Old Adam Toledo Had Gun In Hand When He Was Fatally Shot By Police

(Source: Sun-Times Media Wire © Chicago Sun-Times 2011. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)