Shares of European carmakers fell on Wednesday following a report that some of the world’s largest auto manufacturers face possible lawsuits in Britain for allegedly cheating emissions tests.

Shares of German automaker Porsche slipped over 6% at around 1:15 p.m. London time, falling toward the bottom of the pan-European Stoxx 600 index.

German carmakers BMW and Volkswagen were trading around 1% lower, while Sweden’s Volvo Cars dipped 2.7%.

France’s Valeo and Germany’s Mercedes Benz both traded in negative territory. Fiat-owner Stellantis erased earlier losses to trade slightly higher in afternoon deals.

It comes as the European Union imposed import tariffs on Chinese electric vehicles and after Reuters reported Tuesday that carmakers are facing 1.5 million “dieselgate” lawsuits in Britain that could cost them at least ₤6 billion ($7.65 billion).

Manufacturers including Mercedes-Benz and U.S. carmaker Ford were alleged to have misled customers about some vehicles’ compliance with nitrogen oxide emissions standards, the report said, citing claimants’ lawyers in London’s High Court on Tuesday.

A spokesperson for Ford told CNBC that they see “no merit” in the claims and the carmaker was “robustly defending against them.” They added: “Our vehicles and engines meet all applicable emissions requirements.”

Separately, a spokesperson for Mercedes-Benz said the ongoing hearing “concerns procedural matters related to preexisting emissions-related claims against multiple” original equipment manufacturers.

“We continue to believe that the claims against Mercedes-Benz are without merit and will vigorously defend ourselves against them or any group action with the necessary legal means,” they added.

The “dieselgate” emissions scandal refers to reports that first surfaced in 2015 that Volkswagen had been caught cheating on emissions tests in the U.S. Volkswagen admitted installing so-called “defeat devices” to change diesel vehicles’ emissions levels during testing.

Volkswagen said in 2020 that the scandal had cost the company more than 31 billion euros ($33.3 billion) in fines and settlements.