In the 1980s, Vojislav Šešelj taught political science at the University of Michigan after being expelled by the League of Communists of Yugoslavia in 1981. In June 1989, he traveled to the United States again to meet with Momčilo Đujić in San Marcos, California, where Đujić named him Chetnik Vojvoda ("duke" in Serbian). He went on to form the Serbian Radical Party in 1991 and was accused by the ICTY tribunal of leading the Beli Orlovi militants in Bosnia and Herzegovina and in war-state Republic of Serbian Krajina. Radovan Karadžić pursued post-graduate medical studies at Columbia University from 1974 to 1975, but did so without any specific political agenda at the time being; he later became the war-time president of the Republika Srpska during the Bosnian War and subsequently went into hiding in Serbia until his capture in 2008 for ICTY charges of war crimes and genocide.