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By Aleksandar Vasovic
BELGRADE, Jan 14 (Reuters) - Two former Serbian state security agents were detained on Tuesday over the killing of opposition newspaper publisher and journalist Slavko Curuvija during the rule of strongman president Slobodan Milosevic in 1999.
The arrests arose from a series of investigations, led by the deputy prime minister, into politically-tinged organised crime and corruption as Serbia seeks to improve democratic credentials needed for entry into the European Union.
Miljko Radisavljevic, Serbia's prosecutor for organised crime, told a news conference that former state security operatives Ratko Romic and Milan Radonjic had been arrested in connection with Curuvija's death.
Radisavljevic said a tip-off from Milorad Ulemek-Legija, an imprisoned ex-head of a secret police unit under Milosevic that together with paramilitary gangs targeted his opponents, helped steer police to Romic and Radonjic.
Ulemek is serving 40 years in prison for masterminding the assassination in 2003 of then-liberal Prime Minister Zoran Djindjic, who was a prominent political foe of Milosevic before his fall to a popular uprising in 2000.
"Ulemek testified without asking or receiving any benefits ... I believe the investigation will be over in a month or two and that we will have an indictment," Radisavljevic said.
Lawyers for Romic and Radonjic were not available for comment. A day before his arrest, Romic denied involvement in Curuvija's death. "I am in Belgrade and ... they can arrest me. I will defend myself with the truth that I was not a part of that," Radonjic was quoted by Politika daily as saying.
The Organisation for Security and Cooperation in Europe, the continent's main rights watchdog, welcomed the arrests. "(They) show that progress is only possible when there is clear political will and commitment by the authorities," OSCE media envoy Dunja Mijatovi said in a statement.
Deputy Prime Minister Aleksandar Vucic, who coordinates Serbian security agencies, apologised to Curuvija's family.
"There will be no fooling around and playing with the state ... I am very sad that the investigation took so long," Vucic told the news conference.
"After 14 years prosecutors acquired ... testimony from different sources to confirm the role of the state, the criminal role of the state and individuals who committed such a crime allegedly in the name of state."
Vucic was once a firebrand of the ultra-nationalist Serbian Radical Party and also Milosevic's information minister at the time of Curuvija's killing. But Vucic has since rebranded himself a reformer keen to help guide Serbia into the EU.
Critics have long held Milosevic's security apparatus and inner circle responsible for the shooting death of Curuvija outside his Belgrade flat on Orthodox Easter 1999, when NATO was carrying out air strikes on Serbia over its bloody military campaign against the uprising in its province of Kosovo.
But no one has ever charged with Curuvija's killing.
Milosevic was extradited in 2001 to The Hague for trial before the international war crimes tribunal for former Yugoslavia. He died in 2006 before a verdict could be reached. (Additional reporting by Ivana Sekularac; Editing by)