In July 1995, Lieutenant Višković worked as traffic assistant at the General Staff of the Army of Republika Srpska. According to the ICTY archive documents, on 13 July during the Srebrenica genocide, he was in contact with Colonel Rajko Krsmanović, traffic officer of convicted war criminal Radislav Krstić, about the transfer of captured Srebrenica Bosniaks (including the 700 captured in Sandići) to places such as Bratunac and Zvornik, where they were later shot. ICTY witnesses recall Višković meeting with Krsmanović right before the fall of Srebrenica, and later seeing him near the stadium in Nova Kasaba where captured people were detained. In 2020, a witness testified at the trial of former police officers Miodrag Josipović and Branimir Tešić on Srebenica-related charges in Bosnia, saying that Višković offered him money to dig up a mass grave in Milići in 1996. Public media in Republika Srpska published the identity of the protected witness. Višković rebutted all allegations and announced lawsuits against the media and individuals who published the news.