August Hanning, the former head of Germany’s foreign intelligence service, was arrested on suspicion of treason, espionage and obtaining state secrets. 

Prosecutors allege that Hanning received thousands of classified documents from a former BND aide after leaving the agency in 2005. 

The aide, identified as Manfred D., was also arrested and is accused of supplying Hanning with about 2,000 sensitive documents over several years. 

Investigators believe Hanning used some of the information for private consulting and to prepare an analysis for a foreign intelligence service, whose identity has not been disclosed, The Guardian has reported.

The case could become a major German intelligence scandal because some of the allegedly leaked material included highly sensitive information and material from foreign partner agencies.