Renault, Nissan, PSA, Fiat Chrysler Automobiles and Jaguar Land Rover are all being investigated by the European Commission over possible antitrust violations regarding car parts.

According to news outlet Der Spiegel, the probe is looking into whether or not the companies colluded to raise prices by as much as 25%, with the help of consulting firm Accenture. Allegedly, this investigation started back in December, although the German magazine did not quote any sources.

As of right now, spokespeople for PSA, FCA and JLR have declined to comment, with Autonews Europe stating that representatives from Renault and Nissan could not be reached for comment.

If this report turns out to be accurate, it would mark the European Commission’s second large-scale investigation into European automakers, after its probe into whether VW, Daimler and BMW colluded on clean-emissions technology regarding their cars.

These investigations are really piling up at a time when European automakers are already struggling to figure out what’s going to happen with tariffs on U.S.-bound cars, while a no-deal Brexit scenario could potentially decimate supply chains between the EU and the UK. This new car parts probe would also add to Renault and Nissan’s legal struggles and the two companies are currently dealing with the fallout from the November 19 arrest of former chairman Carlos Ghosn, currently in a Tokyo prison awaiting trial.