A top Bosnian Serb war crimes (search) suspect, indicted by a U.N. tribunal for some of the worst atrocities in the Bosnian war, was arrested Monday in Argentina.

Milan Lukic (search) was being held at a police station in Buenos Aires and was to be questioned by a judge after being arrested in the city on an "international request," according to Argentine Federal Police.

Lukic was indicted by the tribunal in The Hague (search), Netherlands, in 2000 for crimes against humanity. He also has been sentenced to 20 years in prison in Serbia for war crimes but has been on the run since late 1990s.

Lukic — among top war crimes suspects wanted by The Hague court — has been charged with abduction and the killing of 20 Muslims from Serbia that took place in 1993 at a border area.

Earlier this year, Lukic was sentenced in absentia by a Serbian court to 20 years in prison for his role in the abduction of 16 Muslims from a bus in eastern Serbia in 1992.

Lukic, as a member of a notorious paramilitary group — the Avengers — allegedly took part in the abduction of the Muslims, 15 men and a woman, who were later taken to Bosnia, tortured at a local hotel, executed and their bodies dumped in the Drina River.

Two other top Bosnian Serb war crimes fugitives, wartime Bosnian Serb leader Radovan Karadzic (search) and military commander Gen. Ratko Mladic, remain at large.