In various verdicts , the International Criminal Tribunal for the former Yugoslavia ( ICTY ) concluded that Krajina presidents Milan Babić and Milan Martić were cooperating with Serbia 's president Milošević who sent ammunition , financial assistance and the JNA and Serb paramilitary as back up during 1991 and 1992 in order to take over large chunks of Croatia . After the United Nations imposed sanctions against Serbia , the JNA formally withdrew from Croatia by May 1992 . However , in the 2011 verdict regarding Momčilo Perišić , the ICTY established that Belgrade was , through the 30th and 40th Personnel Centre , still supplying armies of Krajina and Republika Srpska all until 1995 , despite international sanctions . In the judgement , the judges ruled that members of the Yugoslav Army served under banners of Military of Serbian Krajina ( SVK ) and VRS , but received pensions , salaries , benefits and promotions directly from Belgrade . Although Perišić did not have effective control over the VRS , he had control of the SVK , but failed to sanction them for the Zagreb rocket attacks
Zagreb rocket attacks
Zagreb rocket attacks
Serbia in the Yugoslav Wars