German authorities arrested a Ukrainian man on suspicion of spying for Russia, according to the BBC and Euronews.

Federal prosecutors announced the arrest Thursday, the outlets reported. Euronews said he was arrested in the state of Brandenburg. Under German privacy law, he was named only as Vadym Y., the BBC reported.

Prosecutors said he had been in touch with a Russian spy agency through a go-between since at least July 2025, the BBC and Euronews reported.

Prosecutors said he gathered facts on how arms are made, the BBC and Euronews reported. That included armored vehicles, ammunition and explosives, they said. Euronews said he also gathered details on staff and military sites that guard NATO's eastern flank.

Some of the information was public, Euronews reported. But prosecutors said he got other details by approaching people in Europe's defense industry, it said.

He was due to go before a judge on Friday, the BBC reported.

Chancellor Friedrich Merz called the case a "success," the BBC reported. But he warned that Russian spying in Germany remains "at a consistently high level," according to the BBC.

Germany has arrested several people this year who are accused of spying for Russia and other nations, the BBC reported. In January, a woman was arrested in Berlin, the BBC said. She is suspected of spying for an officer at Russia's embassy.

Earlier this month, former German spy chief August Hanning was arrested on suspicion of spying, the BBC reported. Investigators have not said which foreign powers were involved, it said.

Germany has been one of Europe's leading suppliers of weapons to Ukraine since Russia's full-scale invasion in 2022, the BBC reported. Euronews said German officials are now warning more sharply about Russian spying and attacks.

What we know: A Ukrainian man is accused of collecting military information in Germany for Russia.
What we don't: How the alleged intermediary recruited him and what he passed on.