A former top FBI official in New York has been arrested over his ties to a Russian oligarch, law enforcement sources told ABC News Monday. Charles McGonigal, who was the special agent in charge of counterintelligence in the FBI's New York Field Office, is under arrest over his ties to Oleg Deripaska, a Russian billionaire who has been sanctioned by the United States and criminally charged last year with violating those sanctions. McGonigal retired from the FBI in 2018. He was arrested Saturday afternoon after he arrived at JFK Airport following travel in Sri Lanka, the sources said.