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Konstantin Kilimnik, a dual Ukrainian and Russian citizen, worked for Paul Manafort’s political consulting firm and ran its office in Ukraine. The Special Counsel’s Office has said Kilimnik has links to Russian intelligence and his interactions with Manafort during the 2016 campaign lie “at the heart” of Robert Mueller’s investigation.

Kilimnik’s background indeed suggests he may have worked for Russian intelligence. He served as a translator for the Soviet military in the 1980s and trained at a military academy known for producing linguists for Russia’s Main Intelligence Directorate (GRU). Those ties may not be solely in the past, either. In court filings, the Special Counsel’s Office has repeatedly referenced the FBI’s assessment that Kilimnik has “a relationship with Russian intelligence” and “had such ties in 2016.”