EU staff had “conducted an inspection” at BMW’s Munich offices this week, BMW carmaker said in a statement to Reuters, adding that it is “assisting the European Commission in its work”.

The EU’s Brussels executive said its antitrust officials had swooped unannounced on “a carmaker in Germany” on Monday Oct. 16 in the first confirmed raid related to allegations that several German automakers had engaged in an illegal cartel. BMW continues to denies those allegations.

Earlier this summer, the antitrust officials said they were investigating collusion among German carmakers in response to a tip-off after Der Spiegel magazine reported that Daimler, BMW, Volkswagen and its Audi and Porsche arms conspired to fix prices in diesel and other technologies over decades.

“The BMW Group wishes to make clear the distinction between potential violations of antitrust law on the one hand and illegal manipulation of exhaust gas treatment on the other,” the company said. “The BMW Group has not been accused of the latter.”

Brussels has yet to initiate formal antitrust proceedings against any of the carmakers.