Almost 30 years ago, Jovica Stanisic and Franko Simatovic trained and directed militias that committed some of the worst atrocities of the post-Cold War era.

In the Balkan wars, their militias are alleged to have conducted massacres at hospitals, razed villages and shot prisoners to help cleanse Bosnia and Croatia of non-Serbs.

Last week, Stanisic and Simatovic — the chief and deputy chief, respectively, of Serbia’s state security services in the 1990s — were sentenced for their crimes by the U.N. tribunal established in 1993 to judge the war crimes committed during the violent breakup of Yugoslavia.