The KGB was the primary security and intelligence agency of the Soviet Union. In the post-collapse Russian Federation, branches of the KGB evolved into the latter-day Federal Security Bureau (FSB) and the Foreign Intelligence Service (SVR), responsible for internal and external intelligence work, respectively.
The First Directorate was a major branch of the KGB. During the Cold War, Borvo Sobrinna, a Serb orphan, was trained by the First Directorate to infiltrate the United States' financial community as a mole. Sobrinna assumed the identity of the deceased Theodore Cofell and became "Ted Cofell." (Findings at CTU)
Victor Drazen's Black Dogs secret police group was known to recruit former KGB operatives for clandestine operations. One of the casualties in the American airstrike against Drazen's compound in Kosovo was Vassili Tupelov, the former KGB director in Belgrade. (Findings at CTU)