Germans investigate Daimler over diesel emissions

BERLIN — German prosecutors searched the offices of Daimler, the automaker that produces Mercedes cars, on Tuesday as part of an investigation into whether the company improperly evaded emissions rules.

The raids signal a deepening inquiry into Daimler, which had already said that several federal and state authorities in Europe and the United States were investigating the emissions control systems used in Mercedes-Benz vehicles.

Prosecutors in the German city of Stuttgart said they had raided 11 off Daimler’s locations, searching for digital and analog documents that could serve as evidence in their investigation of allegations of fraud and illegal advertising in connection with the company’s diesel cars.

In a statement, Daimler said the raids were because of “suspicion of fraud and criminal advertising relating to the possible manipulation of exhaust-gas aftertreatment in passenger cars with diesel engines.”

The company said it was cooperating with the office of the Stuttgart public prosecutor, but it did not comment further.

Unlike Volkswagen’s use of a defeat device, Daimler’s Mercedes division, along with the German engineering company Bosch, developed a technology that relied on using an additional fluid to meet emissions standards.

Known as AdBlue, the fluid was made of a chemical called urea that mixed with engine exhaust to neutralize nitrogen oxide, one of the most harmful diesel pollutants.

Deutsche Umwelthilfe, an environmental advocacy group in Germany has charged that Mercedes cars turn off the system, which is known as BlueTec, when the temperature drops, leading to increased pollution levels.