intel russia espionage

This is the same man whom NATO, in a classified 141-page report, has recognized as the spy who was "most damaging in Alliance history."
Until his arrest, in September 2008, he is believed to have secretly handed over thousands of those documents to the Russians. Some of these contained highly sensitive information about NATO's secret defense policies, "including installation, maintenance, procurement and use of cryptographic systems."
This was the handler's false Portuguese identity. His real name was Sergey Jakovlev, and he was an SVR officer not registered with any embassy. NATO believes that Jakovlev managed an entire network of Russian agents in the Baltics.
According to the classified NATO report, the master spy also "compromised a wide range of NATO intelligence reports and analyses," including ones related to fighting terrorism, secret military plans and counterespionage. Never before, the NATO analysis concludes, has a spy betrayed such a large volume of military secrets for such a long time.

https://www.spiegel.de/international/europe/betrayer-and-betrayed-new-documents-reveal-truth-on-nato-s-most-damaging-spy-a-693315.html