German authorities said they have issued arrest warrants against three citizens on suspicion of spying for China.

The full names of the defendants were not disclosed by the Office of the Federal Prosecutor (aka Generalbundesanwalt), but it includes Herwig F., Ina F., and Thomas R.

"The suspects are strongly suspected of working for a Chinese secret service since an unspecified date before June 2022," the Generalbundesanwalt said.

Thomas R. is believed to have acted as an agent for China's Ministry of State Security (MSS), gathering information about innovative technologies in Germany that could be used for military purposes.

The defendant also sought the help of a married couple, Herwig F. and Ina F., who run a Düsseldorf-based business that established connections with the scientific and research community in Germany.

This materialized in the form of an agreement with an unnamed German university to conduct a study for an unnamed Chinese contractor regarding the operation of high-performance marine engines for use on combat ships.

"At the time of their arrest, the defendants were in further negotiations on research projects that could be useful for expanding China's maritime combat power," the agency said.

"In addition, the defendants purchased a special laser from Germany on behalf of and with payment from the MSS and exported it to China without permission, even though the instrument is subject to the E.U. dual-use regulation."

The development comes as the Generalbundesanwalt announced the arrest of another citizen named Jian G for acting as an agent for the Chinese Secret Service while working for a German Member of the European Parliament since 2019.

"In January 2024, the accused repeatedly passed on information about negotiations and decisions in the European Parliament to his intelligence client," it said. "In addition, he spied on Chinese opposition members in Germany for the intelligence service."

Last week, the Office of the Federal Prosecutor also executed an arrest warrant against a German-Russian citizen Alexander J. for purported secret service agent activity.

The arrests also follow the charging of Christopher Berry, 32, and Christopher Cash, 29, in the U.K. for passing on sensitive information to China in violation of the Official Secrets Act, according to the Metropolitan Police and the Crown Prosecution Service (CPS).

The two individuals, previously arrested on March 13, 2023, from Oxfordshire and Edinburgh, respectively, and later released on bail, have been accused of sharing "articles, notes, documents, or information" which may have been directly or indirectly useful to an enemy nation.

A spokesperson for the Chinese Embassy told BBC News that the allegations amount to "malicious slander" and urged the U.K. to "stop anti-China political manipulation."