Martin Winterkorn, the embattled chief executive of Volkswagen, has announced that he is to resign following the scandal surrounding the emissions of its diesel cars.
In a statement issued by the company Winterkorn said he was "shocked by the events of the past few days."
"Above all, I am stunned that misconduct on such a scale was possible in the Volkswagen Group."
A successor will be determined at Friday's supervisory board meeting. However, rumors earlier suggested he might be replaced by Porsche President and CEO Matthias Muller, Audi chief Rupert Stadler and VW brand head Herbert Diess, although Volkswagen has denied this.
More people can be expected to follow Winterkorn out of the carmaker due to the scandal, a senior VW source who wished to remain anonymous due the sensitivity of the situation, told CNBC.
The world's second-largest carmaker is being engulfed by an emissions scandal which has wiped nearly 26 billion euros ($29 billion) off its market value this week. In this kind of situation, with 11 million cars potentially affected, jobs are put in jeopardy and even once-mighty companies can be permanently damaged.
The speed at which VW moved to clean the slate—five days—stands in marked contrast to the sometimes protracted recalls of other automakers.Toyota, for example, took several years over its recalls.
Volkswagen is said to have been caught cheating on U.S. air pollution tests. VW installed sophisticated software known as "defeat devices" in the electronic control module of diesel vehicles issued between 2008 and 2015.
Winterkorn has become the public face of the scandal, with allegations that he ignored warning signs about the emissions in 2014. In a video on the carmaker's website Tuesday, he admitted, "I do not have all the answers to the questions but we are working hard to find out exactly what happened."
In stepping down Wednesday, Winterkorn said he was "not aware of any wrongdoing on my part" but had accepted the "responsibility for the irregularities that have been found in diesel engines and have therefore requested the Supervisory Board to agree on terminating my function as CEO of the Volkswagen Group."
What's unclear is whether Winterkorn knew about the installation of the defeat devices that allowed the cars to pass official environmental tests. Investors may find it unforgivable if he condoned or ordered their use—but it could be just as problematic if he did not know the devices were installed, as this would suggest a lack of oversight.
The embattled CEO seemed to have clinched a two-year contract extension earlier this year after a leadership battle with longstanding Chairman Ferdinand Piech, who all but publicly criticized the Winterkorn's performance. But Winterkorn won over shareholder support and the showdown saw Piech resign in April.
Winterkorn spent eight years at the helm of Volkswagen, but started his auto career in 1981 at Audi, serving on the board for quality assurance after an engineering stint with Bosch. He joined Volkswagen in the early 1990s in a similar quality-monitoring role, before working in product management, technical development and research roles.
"I have always been driven by my desire to serve this company, especially our customers and employees. Volkswagen has been, is and will always be my life," Winterkorn said Wednesday.
"The process of clarification and transparency must continue. This is the only way to win back trust. I am convinced that the Volkswagen Group and its team will overcome this grave crisis."
After the scandal erupted, shares tanked 18 percent Monday and nearly 20 percent Tuesday. However on Wednesday they pared some losses to trade around 6 percent higher.
Volkswagen has faced other challenges under the CEO's watch, with the most recent sales numbers showing a 1.5 percent drop in vehicle deliveries in the first eight months of 2015 compared to a year earlier and a 5.4 percent year-on-year fall in August alone.
It seems Winterkorn's departure could help provide a clean slate not only for Volkswagen, but for Winterkorn himself, an executive headhunter told CNBC.
Jason Hanold, manager partner of Hanold Associates, which has hired senior leaders for Rolls-Royce, Bridgestone and Harley Davidson, said Winterkorn has a chance to wield his expertise outside the auto sector.
"Private equity and advisory firms would be an exceptional avenue, as his operational and industry knowledge is distinctive, even though his followership will clearly suffer," Hanold said.
As for the future of diesel vehicles, the German auto industry association chief told Reuters that the Volkswagen scandal shouldn't be used as an excuse to question their future.
—Reuters contributed to this report.