The German Federal Prosecutor's office on Monday said three German nationals were arrested under the strong suspicion of having worked for the Chinese secret service.

Prosecutors believe the three may have been involved in research projects that could be useful for China to expand its maritime power.

What are the allegations?

The three suspects, Herwig F., Ina F. and Thomas R., were arrested by officers of the Federal Criminal Police Office (BKA) in the western German cities of Düsseldorf and Bad Homburg.

The defendants' homes and workplaces were also searched.

The charges relate to espionage "at a point in time that cannot be precisely determined before June 2022."

Thomas R. is said to have acted as an agent for an employee of the MSS, the Chinese secret service. 

It is alleged that he obtained information about innovative technologies that could be used for military purposes.

Prosecutors believe he used Herwig F. and Ina F., who were running a company in Düsseldorf, to obtain the information.

The company served as a way to contact and work with German scientists and researchers.

The couple agreed on a deal with a German university on behalf of a Chinese partner on state-of-the-art machine parts for the operation of powerful ship engines that could be used in combat vessels.

The pair are alleged to have violated German Foreign Trade and Payments Act. 

Chinese state authorities are said to have financed the project. One of the accused was allegedly in further negotiations about other research projects for the Chinese navy.

Prosecutors allege the individual bought a special laser from Germany, with payment from the MSS, and exported it to China without authorization, despite the item being subject to the European Union's Dual-Use Regulation.

Last week police arrested two men in the Bavarian city of Bayreuth on suspicion of spying for Russia and seeking to undermine German support for Ukraine.

Soon after news of the arrests, police in the UK said two men had been arrested there on suspicion of passing on sensitive information to China.

How has Germany responded?

German Interior Minister Nancy Faeser said on Monday that the government was monitoring a significant threat posed by Chinese espionage in business, industry and science.

"We look very closely at these risks and threats and have clearly warned and raised awareness about them so that protective measures are increased everywhere," she said in a statement.

Faeser added that the potential use of German innovative technologies for military purposes was "particularly sensitive."

Justice Minister Marco Buschmann tweeted his congratulations to prosecutors for their success."

"This shows once again that we must be vigilant," he said.

Thomas Haldenwang, the head of Germany's domestic intelligence agency, the BfV, told DW the case showed that China, like Russia, is actively engaged in espionage in Germany.

"The [BfV] was involved in the investigation very early on, or we initiated these investigations, and once the evidence was clear, we were able to hand this case over to the police and public prosecutors," Haldenwang said.

The arrests come just a week after Chancellor Olaf Scholz visited China to press the government on its support for Russia's wartime economy and to raise issues of intellectual property theft.

China rejects espionage allegations

The Chinese Embassy in Berlin issued a statement rejecting accusations it was spying in Germany.

"We call on Germany to desist from exploiting the espionage accusation to politically manipulate the image of China and defame China," a spokesperson for the embassy said in an emailed statement.

Editor's note: DW follows the German press code, which stresses the importance of protecting the privacy of suspected criminals or victims and obliges us to refrain from revealing full names in such cases. 

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