WASHINGTON (AP) — An investigation into price-fixing and bid-rigging in the auto parts industry has mushroomed into the Justice Department’s largest criminal antitrust probe ever, and it’s not over yet.

The investigation, made public four years ago with FBI raids in the Detroit area, has led to criminal charges against dozens of people and companies, stretched across continents and reverberated through an industry responsible for supplying critical car components.

The collusion has also saddled U.S. drivers with millions of dollars in extra costs.

“It’s a very, very safe assumption that U.S. consumers paid more, and sometimes significantly more, for their automobiles as a result of this conspiracy,” Brent Snyder, a deputy assistant attorney general in the antitrust division, said in an interview.

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