On 18 September 2015, the United States Environmental Protection Agency (EPA) issued a notice of violation of the Clean Air Act to German car producer Volkswagen Group. The notice was based on the allegation that the car producer had intentionally programmed turbocharged direct injection (TDI) diesel engines to activate certain emission control systems only during laboratory testing. This manipulation had the obvious aim of bypassing the diesel emission standards in the US so as to get the VW diesel cars approved for the US market. Not only the USA with 480,000 vehicles but also Germany with 2.2 million vehicles and many other European countries are affected. VW has admitted that about 11 million cars worldwide, including eight million in Europe, are fitted with the so-called defeat device. VW even sold vehicles with the questionable software in China. Several public prosecutors and environmental protection agencies announce investigations or start investigating. In Germany, the Braunschweig prosecutor and the State office of criminal investigations start searching the offices of Volkswagen in Wolfsburg and other (German) cities.