FRANKFURT AM MAIN (AFP) - Prosecutors in Stuttgart said they raided German sports car maker and Volkswagen subsidiary Porsche on Tuesday (May 28) on suspicion that an auditor was bribed to pass information to the company's tax adviser.

The investigators suspect that "an official from the Stuttgart business audit office revealed confidential information to a tax advisor of Porsche AG and accepted benefits in exchange", they said in a statement.

Almost 200 police and prosecutors searched the luxury carmaker's offices, tax collectors' offices, a tax adviser's office and private homes in and around Stuttgart for paper and digital documents.

On top of the bribery probe, investigators suspect the company made "unjustified" and "disproportionately large" payments to a former works council member.

Six people, including some from the company leadership, "may have committed fraud against Porsche AG", they said.

Earlier this month, Porsche agreed to pay a fine of €535 million (S$825 million) over its role in the separate "dieselgate" emissions cheating scandal.

Its parent company Volkswagen admitted in 2015 to manipulating 11 million vehicles worldwide to appear less polluting in the lab than on the road.