Federal investigators raided the offices of Lumber Liquidators on Thursday, the company and authorities said.
Stocks of the hardwood flooring retailer fell sharply on Friday as the news emerged, dropping just over 10% at midday.
No arrests were made and the the search warrants remain sealed, said Brandon Montgomery, a spokesman for the Department of Homeland Security. He said the search involved special agents from the Immigrations and Customs Enforcement, U.S. Fish and Wildlife Service and the Department of Justice.
Lumber Liquidators suggested the investigation involved its importation of wood products, which come from "approximately 110 domestic and international mills around the world."
"Due to the scale of its international and domestic operations, Lumber Liquidators has policies and procedures in place for the sourcing, harvesting and manufacturing of its products designed to comply with federal and other regulations related to the importation of wood flooring products," the company said. "The Company has more than 60 professionals around the world who perform and monitor those processes."
It said it "takes its sourcing and compliance very seriously, and is cooperating with authorities."
CNN affiliate WWBT reported authorities suspected wood the company said originated in Russia came from elsewhere. It said investigators were searching for emails and other documents. CNN was not able to confirm this report and Lumber Liquidators did not immediately respond to a request for additional information.
Montgomery said the searches took place at the company's Toano, Virginia headquarters, as well as a Richmond location, where the company's products are sold.