In 1993, he became the chief of Pacific Fleet FSB counterintelligence. While in this post, he initiated the prosecution of journalist Captain Grigory Pasko on charges of the collection and storage of allegedly classified documents of the Pacific Fleet, as well as their transfer to the Japanese NHK TV company and Asahi Shimbun newspaper. Pasko was arrested in Vladivostok on 20 November 1997, as soon as he had returned from a trip to Japan.
Pasko insisted that he had only transferred public documents on ecology and that the case had been fabricated by the FSB. He was found not guilty by a court in 2000, but the decision was later overturned, and on 25 December 2001 Pasko was sentenced to four years imprisonment. Ugryumov had already died by the time of Pasko's sentence.