German prosecutors raided Audi office sites across the country on Wednesday as part of the investigation into the emissions cheating scandal that has plagued parent company Volkswagen since 2015. 

Approximately 100 police officers took part in the raids, which began early in the morning at nine of the company's sites, Bloomberg reported. The raids were part of an investigation into the sale of approximately 80,000 Audi diesel vehicles sold in the U.S. between 2009 and 2015 that authorities suspected were outfitted with devices that enabled the company to cheat on emissions tests, Munich prosecutors said. An Audi spokesman told the Associated Press the raids were focused on the company headquarters in Ingolstadt and its plant in Neckarsulm and that the company was fully cooperating with the raids. 

Read: Volkswagen Emissions Scandal Update: Dealerships Win $1.67B Settlement

Audi is owned by Volkswagen, which has admitted it equipped diesel engines with software and devices that reduced emissions when vehicles were undergoing testing. With the systems disabled during regular driving, the vehicles generated 40 times more pollution

In the U.S., Volkswagen has agreed to pay a series of settlements with the Federal Trade Commission that could be worth as much as $14 billion. The carmaker also agreed to buy back or repair all affected vehicles while providing vehicle owners with at least $5,000 in cash sums. Across the U.S. and Canada, the company has agreed to roughly $23 billion in fines, penalties and consumer compensation.

Audi was responsible for designing and manufacturing some of the engines that enabled the Volkswagen to cheat on emissions tests. The raids took place on the same day as the Audi's annual earnings press conference. 

"The path towards clearing up (the emissions scandal) is far from over," Audi CEO Rupert Stadler said on Wednesday. "We will keep at it until this work is done."