German auto giant Volkswagen said Tuesday that as many as 11 million diesel cars worldwide were equipped with a particular engine type that could skew emissions data, as the pollution cheating scandal snowballed.

The automaker also said it was setting aside 6.5 billion euros in provisions in the third quarter to cover potential costs resulting from the scandal and it would have to adjust its profit targets for the current year accordingly. 

The announcement sent VW shares down a further 20 percent on the Frankfurt stock exchange Tuesday, after they lost 17 percent the day before.