Mercedes-Benz parent company Daimler is facing a fine ranging from €800 million (£740m) to €1 billion (£925m) for diesel emission-related violations, according to German magazine Der Spiegel.
Der Spiegel reports the German motor vehicle authority, the Kraftfahrt-Bundesamt, has discovered software deemed to be illegal under existing European Union law fitted to various Mercedes-Benz C-Class and E-Class diesel models, including the popular C220 CDI and E220 CDI.
The software is claimed to allow diesel-powered C- and E-Class models to achieve lower NOx and CO2 emissions in controlled climatic conditions at pre-set speeds on a rolling road during testing than in practice on public roads.
Der Spiegel says Daimler has been ordered to recall up to 280,000 vehicles.
A fine of up to €5000 per vehicle is being considered by the Stuttgart public prosecutor, the German magazine claims.
A spokesman for the Stuttgart prosecutor’s office said the investigation into possible diesel emission fraud by Daimler was continuing and would not be concluded before the end of the year.
Daimler has declined to comment while the investigation is ongoing.
In June, the German motor vehicle authority ordered Daimler to recall 60,000 GLK diesels, bringing the total number of diesel vehicles recalled by the German car maker in relation to software irregularities to more than 760,000.
Daimler also faces prosecution by US authorities. In 2016, the US Environmental Protection Agency asked its Mercedes-Benz division to explain high emissions levels in various diesel models.