General Motors (GM) has filed a federal racketeering lawsuit against Fiat Chrysler Automobiles (FCAU) as part of an ongoing federal corruption probe into union manipulation practices of the automaker.

The lawsuit alleges that Fiat Chrysler engaged in a “multi-year pattern of corruption” by undermining the “integrity of the collective bargaining process,” causing GM “substantial damage.”

“This lawsuit is intended to hold FCA accountable for the harm its actions have caused our company and to ensure a level playing field going forward,” Craig Glidden, GM executive vice president and general counsel, said in a statement.

According to GM, FCA paid millions in bribes to gain benefits, concessions, and advantages in the negotiation, implementation, and administration of the automakers’ union labor agreements over an extended period of time.

GM also claims that Fiat Chrysler corrupted the 2009 collective bargaining agreement as well as the negotiation, implementation, and administration of the 2011 and 2015 union agreements. GM contends this manipulated the collective bargaining process, creating unfair labor costs, and operational advantages, that harmed its business.

GM said it is seeking to recover all damages and will use the compensation to benefit its employees and grow jobs. It is also looking to reinforce the bargaining process to make it free from fraud and corruption.

Three former FCA executives formerly pled guilty in a criminal investigation led by the U.S. Attorney’s General Office in the Eastern District of Michigan, which it said was a clear admission of wrongdoing. Several UAW officials also pleaded guilty to a string of charges in the case.

Shares of GM stock were down 2.97% as of 1:32 p.m. EST on Wednesday while shares of FCA stock were down 3.82% at the same time. 

General Motors The General Motors logo on the world headquarters building is shown in Detroit, Michigan, Sept. 17, 2015. Photo: Bill Pugliano/Getty Images