German prosecutors charge 6 VW staffers over diesel 'fraud'

German prosecutors on Tuesday said they had charged three Volkswagen managers and three employees with fraud as part of their investigation into the massive "dieselgate" emissions cheating scandal.

Brunswick prosecutors accuse the six of knowingly duping customers in Europe and the United States into buying diesel cars rigged with "illegal software" to make them seem less polluting than they actually were.

The six face charges of "serious fraud, indirect falsification of certificates and tax fraud" related to actions between 2006 and 2015, the prosecutors said in a statement.

German prosecutors are investigating dozens of current and former employees over the scandal that erupted in September 2015 when VW admitted to installing software in 11-million diesels worldwide designed to skew emissions tests.

The so-called defeat devices allowed some cars to spew out up to 40 times more harmful nitrogen oxide than legally allowed.

A total of 11 people have now been formally charged over the cheating by German prosecutors, including former VW chief executive Martin Winterkorn who stepped down days after the scandal broke.

The ex-CEO of VW's luxury Audi subsidiary, Rupert Stadler, has also been charged with fraud, falsifying certifications and illegal advertising.

The Brunswick prosecutors said the six latest suspects helped bring vehicles to market that were wrongly certified.

Additionally, in Germany certain vehicles unlawfully benefitted from car tax rebates for being assigned the Euro 6 rating reserved for the newest, and in theory least polluting, diesel engines.

Three of the accused are executives alleged to have played an active role in the scam, while the three other employees "are accused of helping" with the fraudulent acts.

"In particular, they were knowingly and willingly involved in the development, refinement and improvement of the manipulating software," the statement said.

More than four years after "dieselgate", the VW group, which includes the Porsche, Seat and Skoda brands, remains mired in legal woes at home and abroad.

The scandal has so far cost the car behemoth over €30-billion in fines, buybacks and compensation -- including a massive settlement with around 600 000 car owners in the US.

Earlier this month, VW said it would open talks to possibly settle a mass lawsuit in Germany brought by some 400 000 duped diesel owners.