(CNN)A prominent Kosovo Serb politician, Oliver Ivanovic, was shot dead outside his party offices Tuesday morning, halting talks between Kosovar and Serb delegates that had been set to resume that day.
Leading Kosovo Serb politician Oliver Ivanovic shot dead outside office
Ivanovic was shot at least five times outside his office in the Serb-run Kosovar city of Mitrovica, doctors told Serbian State TV RTS.
Emergency services were notified of the attack at 8.17 a.m (2.17 a.m. ET). Ivanovic was transferred to hospital and resuscitated for 45 minutes before doctors confirmed him dead at 9.15 a.m (3.15 a.m. ET).
Ivanovic, the 64-year-old head of the Kosovo Serb Freedom, Democracy, Justice party was due to attend EU-mediated talks between delegates from Kosovo and Serbia in Brussels. The talks are aimed at normalizing relations between Kosovo and Serbia.
Kosovo declared independence from Serbia 10 years after the bloody conflict between Serb forces and Kosovar-Albanian rebels. Serbia does not recognize Kosovo as an independent country.
However after Ivanovic's death, the Belgrade delegation left Brussels to return to Serbia, the Serbian government said in a statement.
Regional Chief of Police for Northern Kosovo, Zeljko Bojic, said in a statement that at 9:15 a.m. a burned out Opel Astra vehicle was found, with special units conducting an investigation of the site.
Serbian President Aleksandar Vucic described the murder as "an act of terror" and vowed to find those responsible.
"Serbia will take all necessary measures, and I promised the same to Oliver Ivanovic's wife, and we will find the killer or killers," Vucic said in a statement following an emergency meeting of the National Security Council.
Vucic said that Serbia had made a request to EU and UN missions in Kosovo to participate in the investigation.
The Head of the Organization for Security and Co-operation in Europe (OSCE) Mission in Kosovo, Jan Braathu, said the murder was "profoundly distressing" and a "major test for the rule of law in Kosovo."
"He (Ivanovic) was among the most prominent Kosovo Serb representatives for almost two decades," Braathu said. "He demonstrated relentless engagement for the benefit of his community and has been a valued interlocutor in Kosovo."
"I have had the privilege of knowing him personally over the years and have always admired his intellect, composure, and commitment. To see that a politician can be murdered in cold blood in 2018 in Kosovo is a devastating thought."
Ivanovic was facing a retrial for alleged war crimes against ethnic Albanians during the Kosovo war.
The war between 1998 and 1999 led to thousands of deaths and the displacement of nearly 90% of Kosovo's population.
This story has been updated to clarify the details around Ivanovic's death.