French Carmaker Renault’s Shares Drop After Emissions Probe

French authorities have raided the offices of the country’s largest carmaker, Renault SA in connection with a probe into excess emissions by its vehicles.

News of the raids, which were first leaked to the news agency AFP by that CGT labor union and then confirmed by Renault, sent the company’s stock crashing by as much as 20% Thursday as investors prepared for a re-run of the emissions scandal around Renault’s German rival Volkswagen AG.

After the Environmental Protection Agency issued a notice of violation against VW in September for using rogue software to mask the true level of harmful emissions of nitrogen oxides and particulate matter from some of its diesel engines, the French government commissioned an inquiry of its own into whether French carmakers, too, had employed similar tactics. Over half of the cars made by Renault run on diesel engines.

Renault said that the “Royal Commission” (named after Ségolène Royal, the current Minister for Ecology, Sustainable Development and Energy) had ordered the officially recognised testing and research center UTAC to test a cross-sample of 100 vehicles currently in circulation in France, 25 of which were Renault’s (reflecting its share of its home market).

Renault said in a statement that four of its vehicles, all diesel, had already been tested, “something which has allowed the French authorities to engage in an informed and fruitful (“nourri et fructueux“) dialogue with Renault’s engineers.” It added it was “cooperating fully” with the investigation.

Renault said that the government body running the tests had indicated it didn’t think it likely that ‘defeat devices’ similar to those used by VW would be discovered. The company itself has already denied using defeat devices.

Renault’s statement helped the shares to recoup half of their losses, but they were still down by over 9.2% by 1500h in Paris, making it by far the worst-performing share locally. Shares in its biggest local rival Peugeot SA were down 3.7%.

If the commission has discovered anything similar to what the Environmental Protection Agency discovered at VW, then Renault’s description of the ‘dialogue’ with the authorities may be hard to beat as ‘Business Euphemism of the Year.’ The ‘dialogue’ led to raids at three Renault sites–its headquarters, and its technical center in Lardy and Guyancourt. AFP reported CGT officials as saying that computers and data storage appliances were removed during the raids.

A spokeswoman for Renault couldn’t immediately say whether the company used the same on-board diagnostic equipment for regulating emissions that VW had sourced from component maker Robert Bosch GmbH. Bosch has said that it sold the software to multiple companies, but that it was up to the client to instal it and set its operating parameters.

The Environmental Protection Agency hasn’t issued any Notices of Violation to Renault about breaking U.S. regulations.

This article originally appeared on Fortune.com