Stadler is the most senior company official to be detained so far since Volkswagen (VW) admitted in September 2015 to using illegal software to rig US emissions tests on diesel engines.
Munich prosecutors, who widened their probe into Audi earlier this month, said Stadler was being held due to fears he might hinder their investigation into the scandal, plunging VW into a leadership crisis.
“We need to find a solution for Audi’s leadership for the time when he is not here,” the source familiar with the talks said about Stadler’s position. “We will comment on this later.”
VW and Audi directors were discussing the leadership crisis in separate meetings yesterday, with one source saying Dutchman Bram Schot was the front runner to become interim Audi chief.
Germany’s Sueddeutsche Zeitung newspaper said VW’s supervisory board had already picked Schot for the job and only needed the formal approval of Audi’s directors.
VW denied any such appointment had been made.
VW has set aside around $30bn to cover fines, vehicle refits and lawsuits since its “dieselgate” scandal broke, and has announced plans to spend billions more on a shift to electric vehicles as it seeks to rebuild its reputation.
Whereas group CEO Martin Winterkorn resigned in the days after the cheating was disclosed, Stadler has remained in post and was this year promoted by new VW boss Herbert Diess in an overhaul aimed at speeding up the group’s reforms.
“His arrest is another low point in VW’s diesel saga,” said Evercore ISI analysts, who have criticised the group for a slow pace of reform. “Almost three years after the diesel scandal broke, it takes police to take action against the Audi CEO.”
The US filed criminal charges against Winterkorn in May, but he is unlikely to face US authorities because Germany does not extradite its nationals to countries outside the European Union.
The Munich prosecutors said the move against Stadler was not made at the behest of US authorities.
The 55-year-old was arrested at his home in Ingolstadt in the early hours yesterday, they said.
“The arrest warrant was made because of a risk that evidence might be suppressed,” Stephan Necknig, a spokesman for the Munich prosecutor’s office, told Reuters Television.