The U.S. Federal Trade Commission has filed a VW emissions lawsuit against Volkswagen in San Francisco federal court over claims of false advertising.

According to the Wall Street Journal, the FTC is investigating the advertising practices of the German auto giant after it was discovered that vehicles promoted as being environmentally friendly were actually installed with defeat devices that allowed the vehicles to pass emissions tests.

The FTC false advertising lawsuit will join all other VW diesel emissions fraud lawsuits, meaning the government agency will be included in any settlement resolutions that come from the civil litigation.

The court has given VW until April 21, 2016 to come up with a plan regarding how the company intends to fix the vehicles.