A British national, known only as David S, has been arrested in Germany on suspicion of spying for Russia. The man worked at the British embassy in Berlina where he allegedly passed documents to Russian intelligence in exchange for money. The documents that David S sold remain unspecified and it is unclear how much money he received for the exchange. David S was arrested in Potsdam outside of Berlin on Tuesday and his workplace and home have been searched by German authorities. Berlin stated that they are taking the case very seriously, asserting that spying by a close alliance on German soil was unacceptable.

The arrest came as a result of a joint UK-German investigation that detected suspicious behavior from David S. The intelligence-led investigation had been ongoing for several months leading up to the arrest, according to officials. MI5 and other UK agencies had been working with German intelligence agencies to uncover as much information as they could about the case before the arrest. London’s Metropolitan Police confirmed the arrest. The man is set to appear before an investigating judge on Wednesday.

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