Germany's federal prosecutors' office says a member of the BND intelligence agency has been arrested on suspicion of spying for a foreign country.
Prosecutors did not name the country, but Der Spiegelmagazine identified it in an online report as Bulgaria.
The federal prosecutors' office in Karlsruhe today said in a statement the 64-year-old member of the Bundesnachrichtendienst (BND) was suspected of giving secret documents to a female foreign agent between 1999 and September 2003.
Der Spiegelsaid the man was a BND Balkan specialist and described him as an alcoholic.
Its report said the German government was outraged over the alleged spying by a friendly nation. Bulgaria is a candidate to join the European Union in 2007.
A German government spokesman declined to comment, and the Bulgarian embassy could not be reached for reaction.