No arrests were made, but some of the people whose homes were searched have been subpoenaed to appear before a federal grand jury.
The activists who were targeted say they have done nothing wrong. Supporters say the raids will have a chilling effect on civil liberties.
Joe Iosbaker and his wife say they've marched, protested, and organized on behalf of several causes. But because they're scheduled to appear before a grand jury next month, they couldn't say what specifically about their work has drawn the FBI's attention.
"We have done nothing wrong," Joe Iosbaker said to a crowd gathered Saturday.
Joined by dozens of supporters and activists, Joe Iosbaker and Stephanie Weiner denounced the FBI search of their home.
"These raids, searches, and grand jury investigations are nothing more than an attempt to intimidate us and to intimidate the anti-war movement," said Iosbaker.
The couple's Northwest Side house was one of two in Chicago raided by the FBI Friday. Agents also searched five homes and an office in Minneapolis as part of a grand jury investigation into "activities concerning the material support of terrorism," an FBI spokesperson said.
The FBI hasn't said what their raids turned up, but Iosbaker and Weiner say agents took more than 30 boxes of papers and personal items.
"They took documents showing their political involvement in the 70s, the 80s, and the 90s. They took baby cards. They took postcards from old girlfriends," said Melinda Power, attorney for Iosbaker and Weiner.
Iosbaker is a union steward for the SEIU, and he and his wife have been outspoken critics of the wars in Afghanistan and Iraq, as well as of the United States' support for Israel and Colombia.
"All we ever did was work against U.S. military aid to the governments of Colombia and Israel and to support the peoples of Colombia and Israel in their struggle for justice," said Iosbaker.
"It's really about silencing a strong movement and intimidating a strong movement," Weiner said.
But other than marching and organizing, the couple and their attorney declined to offer specifics about their work, including where they've traveled.
"You can't confirm whether or not you've been overseas?" asked ABC7 Chicago's Eric Horng.
"I've just said we will not be answering those questions because there's a pending grand jury," answered Attorney. Power.
The Chicago office of the FBI also said it couldn't comment on the details of the affidavit that led to the search warrants and subpoenas.
Activists see an opportunity with these searches to raise awareness about their causes. They've already scheduled two demonstrations in Chicago: one on Monday and another next month.