A Munich engineer has been arrested on suspicion of spying for Russia, reportedly selling secrets from the Eurofighter project.
The German embassy in Moscow is said to be preparing a letter of protest to the Russian government. But security services in Bonn deny that he was selling information about the Eurofighter, saying instead that he was dealing in details of tank weaponry.
A news magazine, Focus, reported that the 52-year-old man, named only as Mr Peter S, and who worked for a subsidiary of DaimlerChrysler Aerospace (Dasa), had passed Eurofighter rocket information to one of Russia's leading spies.
The report claims that the duo were reported to the secret services by a former member of the East German communist secret service, the Stasi.
Mr S's Russian contact, named only as Mr Michael K, had been living in the small town of Soltau, near Hanover, as a transport businessman, according to Mr Rolf-Peter Minnier, president of the Lower Saxony regional office of the Protection of the Constitution, Germany's equivalent of the British MI5.
The Dasa spokesman, Mr Rainer Ohler, confirmed Mr S had worked in the tank weaponry section of a subsidiary company, Lenkflugkoerper-Systeme GmbH. There has been no decision about the arming of the Eurofighter, he said.
Mr Ohler did confirm studies were being prepared on possible weapons systems for the Eurofighter. It is these that the Focus report claims were being passed to Russia.
Charges against Mr S are being prepared by the state prosecutor for allegedly passing military secrets to a Russian handler over a period of four years. He was arrested at the end of July in a double manoeuvre by security chiefs who arrested his 39-year-old alleged accomplice on the same day at Hanover airport.