FRANKFURT (Reuters) - Prosecutors and tax authorities on Tuesday raided the offices of several senior officials of Volkswagen (VOWG_p.DE), the German car-maker said. Investigators searched the offices of supervisory board chairman Hans Dieter Poetsch, finance chief Frank Witter, and human resources head Karlheinz Blessing, a Volkswagen spokesman said. Files and computers were seized. The raid was related to suspicions of overpayments for works council chief Bernd Osterloh, the spokesman said. Osterloh s office was also searched.  Neither the works council nor the prosecutor in Braunschweig were immediately available for comment. A person with knowledge of the matter said the tax authorities were acting on suspicion of tax evasion. That is because over-remuneration could result in overly high operating expenses and the payment of too little tax. It was revealed earlier that German prosecutors were investigating current and former executives at Volkswagen on suspicion that they paid works council chief Bernd Osterloh an excessive salary.  In Germany, wasting corporate funds is legally a breach of fiduciary duty. 