FBI agents removed boxes of documents and other items Friday from the State House office and the Providence home of House Speaker Gordon Fox.
Officials would not say who or what was being investigated, but it did not appear to be connected to Fox's private law practice.
The U.S. Attorney's Office said two federal search warrants were executed in connection with a law enforcement action between federal and state officials, including the FBI, the Rhode Island State Police and the IRS. It did not say where the warrants were executed.
NBC 10's Parker Gavigan reported that the search warrants and affidavit are sealed.
Larry Berman, Fox's spokesman, said he and two other staffers were the only ones in the State House office when agents and troopers arrived. The General Assembly was not in session, and Fox was not at the State House.
"All I know is that the state police came in. There were some other law enforcement officials, and they asked us all to leave. They cleared out, asked us to clear out," Berman said.
Berman said he does not know what the raid was about.
"The speaker I would assume does, but I don't," said Berman, who added he hadn't talked to the speaker Friday.
Berman said he wasn't aware if Fox had any plans to resign.
Fox was dropped off at his East Side home after agents had gone and did not say anything to reporters. He walked into the house quickly and shut the door.
Fox, 52, has served in the House of Representatives since 1993. He has been speaker since February 2010.
In January, Fox agreed to a settlement with the state ethics commission for failing to disclose he had done more than $40,000 in legal work for a Providence economic development agency. Fox acknowledged breaking a law that requires elected officials to annually report whether they received more than $250 in income from a government agency and agreed to pay a $1,500 civil fine.
Albin Moser, a lawyer who represented Fox in the recent complaint before the state ethics commission, wouldn't comment on Friday's events or say whether he is still representing Fox.
The Associated Press contributed to this report.