Germany has arrested a national on charges of spying for the Chinese secret service and leaking information from the European Parliament, Germany's federal prosecutor's office said on Tuesday.

The man was also accused of spying on members of the Chinese opposition in Germany, according to a CNBC translation.

The alleged spy was named as Jian G. and identified as an employee of a German member of the European Parliament since 2019.

Local media has reported that the MEP in question is Maximilian Krah of the far-right AfD. Their offices are reportedly next to each other in the parliament in Brussels, but the alleged spy has not been seen there, local media was told.

CNBC could not independently verify this information.

A spokesperson for the AfD told CNBC that reports of the arrest of Krah's employee are "deeply concerning," according to a CNBC translation, without directly confirming whether such a detainment had taken place. The party would do everything to support the investigation, the spokesperson added.

"In January 2024 the accused repeatedly shared information about negotiations and decisions in the European Parliament with his intelligence service employer," the German federal prosecutor's office said in a statement, according to a CNBC translation.

G. was arrested on Monday, according to the prosecutor's office, and a judge is set to decide about an arrest warrant and custody arrangements on Tuesday. The allegations follow an investigation by German domestic intelligence services.

"If it is confirmed that there was espionage for Chinese intelligence services from within the European Parliament, then that would be an attack on European democracy from within. Whoever employs such a person carries responsibility," Nancy Faeser, German interior minister, said in a CNBC-translated post on social media platform X.

Separately on Monday, three other German nationals were arrested on charges of sharing information pertaining to German research about new technologies that have a military use with China's secret service, the federal prosecutor said.

The Chinese Embassy in Germany did not immediately respond to a CNBC request for comment.

The Chinese Foreign Ministry on Tuesday rejected claims of espionage in Germany, saying the "hype" surrounding such accusations is aimed to discredit and suppress China, Reuters reported. The ministry also said it hoped that Germany would stop using the so-called spy threat to manipulate political narratives, according to Reuters.

Elsewhere, two U.K. citizens were also charged for allegedly spying for China on Monday.

Correction: This article has been updated to reflect the timeline of when the two U.K. citizens were charged with alleged espionage.