BERLIN, Aug. 17 (Xinhua) -- Former Volkswagen chief executive officer (CEO) Martin Winterkorn and the company's acting CEO Herbert Diess have both been incriminated in testimonies made by staff during the ongoing "dieselgate" investigations, popular German magazine Spiegel reported on Friday.
According to Spiegel, four technicians and former managers who are formally charged with criminal offenses in the scandal told prosecutors that Winterkorn and Diess withheld relevant information about emissions-cheating practices from the public.
The testimonies all state that Winterkorn and Diess were made aware of the installation of illicit defeat devices to understate nitrogen oxide (NOx) emissions by July 2015 at the latest. Nevertheless, they claimed the two senior managers refused to alert regulators and shareholders.
At the time, Winterkorn was CEO of the publicly-listed Volkswagen Group, while Diess occupied the helm of its flagship Volkswagen brand.
The four employees specifically referred to a meeting of around a dozen senior managers who discussed key aspects of illegal software in diesel vehicles and potential fines suffered by Volkswagen in the United States as a consequence.
Slides were allegedly presented to the attendees who detailed the scale of the emission fraud in the country several weeks before the company began to cooperate with U.S. authorities after the international scandal was revealed.
Volkswagen rejects the allegations against Winterkorn and Diess.
The company insists there was merely a small informal meeting around the time in which potential issues with diesel motors in the United States were flagged as requiring a technical response.
Management was therefore not made aware that the installation of the defeat devices amounted to criminal fraud under U.S. law.
So far, Diess and Winterkorn have refused to comment in public on ongoing investigations into their involvement in the diesel emissions scandal.
However, Diess told press that he had offered to travel personally to the United States to help resolve the matter with local authorities.
Winterkorn stepped down from his position at the helm of the Volkswagen Group shortly after the first reports about the "dieselgate" scandal were published in September 2015.
He has repeatedly stated that he had no prior knowledge of emissions cheating practices affecting 11 million vehicles at his company.
The Braunschweig State Prosecution Office currently lists 49 suspects in its investigations into emissions-cheating at German car makers.
A small number of senior Volkswagen executives, including Winterkorn, his successor Diess and board chairman Hans Dieter Poetsch are believed to have potentially committed "market manipulation" offenses under German laws governing the conduct of publicly-listed companies.
Also on Friday, German newspaper Bild reported that Volkswagen was preparing to sack several staff members who were listed as "dieselgate" suspects.
Bild cited information that immediate dismissal notices sent by mail were already on the way to affected individuals, marking a U-turn in Volkswagen's handling of the crisis after having previously shown leniency towards staff which had not been formally found guilty of wrongdoing.
Stadler's arrest marked the first time that a member of the management board of a German car maker was taken into police custody in the "dieselgate" scandal.
The Audi CEO has since provided a first testimony to prosecutors at the penitentiary facility near Munich. It remained unclear on Friday whether he, too, was among the four individuals who have made incriminating statements against Winterkorn and Diess.
