Investigators have raided the home and office of Klaus Zumwinkel, Deutsche Post chief executive officer and one of Germany's most influential businessmen, and questioned him before he was released on bail.

German prosecutors said he was suspected of not paying €1m euros (£750,000) in taxes, using banks in Lichtenstein. Zumwinkel, who led Deutsche Post since 1990 and oversaw its flotation in 2000, is not expect to have his contract renewed when it expires later this year, BBC News reports.

A statement to investors yesterday said the entire board of directors, including Zumwinkel, ‘is fully functional and continues its business as usual’.

A spokesman for the Social Democrats, which forms part of Germany's governing coalition, said that, if Zumwinkel were found guilty, he should ‘not hold his job for one minute longer’. ‘It is beyond comprehension that a multimillionaire like Zumwinkel found it necessary to save a couple of million euros in this way,’ Rainer Wend told Der Spiegel magazine.

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