The claims, originally made on a television news programme earlier this week, were acknowledged by Volkmar Kallenbach, a spokesman for the Darmstadt public prosecutor's office. He said his office had received a statement from a VW secretary.
In the news programme, the secretary, who was not named, was reported to have said she had been instructed to input data about Opel into the Volkswagen computer system by Jose Ignacio Lopez de Arriortua, VW's production chief and the man at the centre of a furious row between the two car manufacturing giants.
Although Mr Kallenbach declined to comment on the veracity of the claims, their mere existence adds to the suspicions surrounding Volkswagen and the allegations of industrial espionage levelled against Mr Lopez by GM, the company for which he used to work until March.
In a swift damage limitation exercise, Volkswagen once again denied the charges and any knowledge of the latest claims. 'We are not aware of the reported testimony quoted by ZDF (one of the main German television networks) by a VW employee to a third party,' the company said in a statement. 'We are only aware that several VW employees testified as witnesses at the Darmstadt public prosecutor's office.'
Although Volkswagen has consistently insisted that Mr Lopez and the other former GM employees who defected with him in March did not bring sensitive industrial secrets with them, the denials have assumed an increasingly threadbare air.
Earlier this month, Mr Piech, whose future is now considered by many observers to be totally intertwined with that of his controversial number two, Mr Lopez, tried to maintain that the US General Motors was deliberately seeking to defame VW and damage German industrial interests.
Last Friday, however, the VW supervisory board took a more conciliatory line, admitting for the first time that the defectors might indeed have brought confidential documents with them. But it said these had all been shredded before they could fall into VW's hands.
Lutz Schilling, a VW spokesman, said earlier this week that the documents Mr Lopez brought from General Motors were simply 'personal things belonging to Mr Lopez - things every man or woman would have in their offices, such as books, documents, old presentations and such like'.
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