Former head of Germany’s foreign intelligence service August Hanning was arrested Tuesday on suspicion of passing state secrets to a foreign intelligence service, the federal prosecutor’s office said.

Hanning, 80, who headed the Federal Intelligence Service (BND) from 1998 to 2005, is strongly suspected of treasonous espionage, spying out state secrets, attempted treason and espionage, prosecutors said.

He was arrested in Bad Toelz-Wolfratshausen in southern Germany.

A former aide, identified as Manfred D., was also arrested in Steinfurt in western Germany and charged with aiding and abetting attempted treason and treasonous espionage.

Federal prosecutor’s office spokesperson Ines Peterson told German broadcaster RTL that Hanning is suspected in one instance of using classified information to prepare an analysis for an employee of a foreign intelligence service.

In another case, he allegedly passed on information following an extensive exchange with an employee of another intelligence service.

Authorities did not disclose which foreign intelligence services the two men allegedly worked with or which countries were involved.

Properties belonging to both suspects were searched Tuesday.

Prosecutors said Manfred D. served as Hanning’s chief of staff and later held the same position for several BND presidents between 2012 and 2026. His position gave him access to confidential information.

According to prosecutors, the two men allegedly agreed in 2010 that Manfred D. would continuously provide Hanning with valuable BND intelligence in return for payment.

Investigators believe Manfred D. supplied Hanning with about 2,000 documents over the years, many of which contained classified information intended solely for internal BND use, particularly executive intelligence briefings.

Peterson said Hanning used the information for private consulting work, while Manfred D. continued providing classified material until June 2022.

The investigation leading to Tuesday’s arrests emerged from a separate probe into the January 2024 abduction of the children of Hamburg businesswoman Christina Block from their father in Denmark amid a long-running custody dispute.

Evidence uncovered during a search of Hanning’s home in connection with that case led to the current proceedings, prosecutors said.

Hanning and a retired official of the Hamburg State Criminal Police Office were suspected of accepting a contract from Block in 2022 to abduct her children while working as executives of a security company, German news agency dpa reported, citing prosecutors’ announcement in late 2025.

The Block family is prominent in Hamburg and is best known for the nationwide Block House steakhouse chain. The custody dispute has drawn considerable media attention in Germany.

A request for comment from the BND was not immediately answered.

Konstantin von Notz, a lawmaker from the opposition Greens party and a member of the parliamentary committee overseeing Germany’s intelligence services, called for a swift investigation.

He described the allegations against Hanning as “hard-hitting and deeply troubling” and said authorities should conduct a thorough probe.

Von Notz also renewed calls for restrictions on former senior officials with high-level security clearances taking up private consulting work after leaving government service.