The appointment steps up the inquiry into payments made to the family of the presidential candidate.
The former Australian and New Zealand internationals were buying cocaine, police sources say.
German intelligence spied on the BBC and other foreign journalists, Spiegel news reports.
Malaise in the French countryside ahead of presidential vote
The Social Democrat seeking to oust Chancellor Merkel
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Why the Turkish government says 'no' to the word 'no'
The film shining a light on a Ukrainian tragedy
Is Malmo the rape capital of Europe?
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Do you shop with your purse or your heart strings?