The competition authorities of the EU and Great Britain carried out unannounced searches at various manufacturers and interest groups in the automotive industry on Tuesday.
According to its own statements, the EU Commission requested information from several companies at the same time.
The agency said it suspected several manufacturers of violating competition rules.
The British regulator said it was dealing with agreements to recycle depreciated cars that would be classified as scrap.
There are regulations that these must be disposed of sustainably.
The manufacturers would have to offer their customers free recycling of these vehicles, which is usually outsourced to service providers.
Neither authority gave details.
They emphasized that it was not yet clear whether antitrust rules had been violated.
Star witness Mercedes?
It has not been announced which companies are affected.
VW declined to comment.
BMW stated that it had received a request from the authority.
However, no search took place.
Mercedes seems to get away with it.
The company cooperated "early and comprehensively" with the EU Commission and the British supervisory authority as a key witness and "does not expect any fines in this matter," the manufacturer said.
Renault confirmed "that a visit by investigators from the European Commission took place today".
Upon request, Opel also announced that business premises had been searched by representatives of the EU Commission.
The parent company Stellantis did not immediately respond to a request.
There have been a number of cartel proceedings in the automotive industry in recent years.
In July last year, the Commission imposed a fine totaling almost 900 million euros on VW and BMW.
Mercedes did not have to pay a fine due to the leniency program.
The Commission complained about collusion in the after-treatment of exhaust gases in diesel cars.
The manufacturers would have colluded regularly, restricted competition and prevented innovations.
In 2017, the EU imposed a billion-dollar fine on truck manufacturers.