According to German media reports on Wednesday, police officers and prosecutors searched offices at Audi headquarters in the Bavarian city of Ingolstadt, as well as offices in the states of Baden-Württemberg and Lower Saxony. Private residences were also searched. 80 police officers and prosecutors were involved.

Audi later confirmed the raids, saying in a statement that it would "fully cooperate" with the authorities.

Prosecutors in Munich have long been investigating whether the Volkswagen subsidiary could also be held responsible for the so-called Dieselgate scandal that erupted in 2015, when it emerged that 11 million cars worldwide had been equipped with software to deceive emissions tests.

More than two million Audis had the manipulated software, including more than half a million in Germany alone.

A former head of diesel engine development, Ulrich Weiss, has accused Audi boss Rupert Stadler of knowing about the engine manipulation early on. However, German prosecutors said they were not investigating specific Audi managers, with the charges leveled at persons unknown so far.

The US government and VW have agreed on a so-called statement of facts recently, including accusations that Audi engineers designed a 3.0 liter diesel engine for the American market equipped with a so-called defeat device designed to mislead authorities and customers on emissions.

The engine is said to be used in several car models of VW, Audi as well as Porsche. According to the US indictment, the Audi A6 Quattro and the A7 Quattro are affected as well as the SUVs Q5 and Q7.

uhe/kd (dpa, AFP)