VW says 'around 50' witnesses have come forward in internal probe

Around 50 employees of German auto giant Volkswagen have come forward to testify in the group's internal probe into a massive pollution-cheating scandal, a spokesman said on Tuesday.

"Up until yesterday's deadline, around 50 employees have taken part in the internal witness programme," the spokesman told AFP.

VW has launched an internal investigation into its biggest-ever scandal after the carmaker was forced to admit in September that it had installed software in 11 million diesel engines worldwide enabling them to cheat in emission tests.

Employees had been given until Monday to come forward to testify without fear of repercussions on the part of VW.

The so-called defeat devices turn on pollution controls when the car is undergoing testing, and off when it is back on the road, allowing it to spew out harmful levels of nitrogen oxide.

The revelations have sparked investigations in several countries but they turned out to be only the beginning as Volkswagen also admitted that it also understated carbon emissions, for 800,000 vehicles.

The company has said the revelations have had an impact on car sales, with demand for the group's 12 brands -- including Audi, Skoda and Porsche -- falling.