Around 100 German police officers on Monday raided about 30 locations linked to US automaker Ford in the Cologne area: Ford plants, an unidentified company in Leverkusen and employees' private homes.
The state prosecutor's office said it had for months been working on the investigation involving Ford staff and others suspected of corruption, breach of trust and fraud.
"We arrested one person," said Cologne prosecutor Christina Pohlen.
Ford staff are suspected of regularly receiving "material advantages" from companies that work with the automaker or which sought contracts with it.
In exchange, the automobile workers allegedly favored benefactors when contracts were being decided upon or established false or excessive bills in their favor.
Prosecuters said Ford had from the start cooperated closely with the authorities and was keen to clear up the allegations quickly.
Author: Dagmar Breitenbach (dpa, AP, AFP)
Editor: Rob Turner