August Hanning, who led German Intelligence from 1998 to 2005, was arrested on Tuesday along with his former chief of staff, who served until 2006, on suspicion of espionage.
According to Der Spiegel, they allegedly used and transmitted classified documents to draft an analysis intended for a foreign intelligence service, possibly Azerbaijani.
This case embarrasses German intelligence agencies, which are seeking to strengthen themselves against Russia, as confidence in their security is undermined.