The Federal Bureau of Investigation conducted a series of raids on Wednesday as part of an investigation into corruption within the U.S. auto industry, searching the Detroit home of United Auto Workers President Gary Jones and the California home of former President Dennis Williams, according to The Detroit News. The raids across at least three states are part of a years-long investigation into corruption including alleged “bribes, kickbacks, and attempts by auto executives to influence labor negotiations with the UAW.” So far, charges have been brought against nine people with links to the UAW and Fiat Chrysler Automobiles NV.

The Wednesday raids were at multiple locations, including the 1,000-acre UAW Black Lake Conference Center in northern Michigan, which was financed by interest from the union’s $721 million strike fund.