As part of a lengthy investigation into allegations of between the and Fiat Chrysler, federal agents conducted a series of raids across at least four states today.

The Detroit home of current UAW president Gary Jones and California home of ex-president Dennis Williams were raided today, reports the . From the story:

Federal agents fanned out to execute search warrants at multiple locations, including Jones’ home in Canton and at the UAW Black Lake Conference Center, a 1,000-acre retreat in northern Michigan financed with interest from the union’s $721 million strike fund, which is bankrolled by worker dues.

Mara Schneider, public affairs officer for the FBI’s Detroit branch, said there are several search warrants being executed Wednesday across the country, including two in Michigan. She said she couldn’t give a total number of warrants being executed by the FBI, the IRS Criminal Investigation Division and the Department of Labor’s Office of Inspector General.

UAW spokesperson Brian Rothenberg told the outlet he believe the raids “unnecessary.” He said:

“The UAW and President Gary Jones have always fully cooperated with the government investigators in this matter. As the leader of the UAW, President Jones is determined to uncover and address any and all wrongdoing, wherever it might lead.”

“There was absolutely no need for search warrants to be used by the government today — the UAW has voluntarily responded to every request the government has made throughout the course of its investigation, produced literally hundreds of thousands of documents and other materials to the government, and most importantly, when wrongdoing has been discovered, we have taken strong action to address it.”

Former federal prosecutor and current Wayne State University law professor, Peter Henning, however called the raids “a very serious step.” He said, “You execute a search warrant because you are worried evidence might disappear... it indicates that the Justice Department doesn’t trust that it will get all of the material that it wants by sending out a subpoena.”

In July of last year, the reported Williams allegedly told senior UAW officials to “use funds from Detroit’s automakers, funneled through training centers, to pay for union travel, meals and entertainment.”

The action is just another development in the multi-year scandal that found high-ranking UAW executives embezzling money from the organization to fund .

These raids come as the UAW is currently undergoing contract negotiations between its members and Detroit’s Big Three. It’s unclear whether or not they will affect negotiations, but tensions have already been high this year following the scandal, fast-changing automotive landscape and looming recession.

As of now, nine UAW and FCA officials have been charged in the scandal, including ex-vice presidents and General Holiefield and . Jewell has been for accepting bribes from FCA.