International judges Monday ordered two Serbian former state security officials back to jail ahead of their retrial, after quashing their acquittals on war crimes charges from the 1990s Balkan conflicts.
Former head of Serbia's state security service Jovica Stanisic, 66, and his deputy Franko Simatovic, 67, were both ordered "to return to the United Nations Detention Unit in The Hague by Tuesday, 30 May 2017."
Their retrial "is anticipated to start on June 13, 2017," said the judges at the tribunal based in Dutch city.
The court is handling cases left over from the International Criminal Tribunal for the former Yugoslavia (ICTY), which is set to close this year.
After some 17 months of freedom, the two men will now go on trial again.
The court denied requests to extend their provisional release, which was granted in December 2015.
It also ordered Serbian authorities to hand them over to Dutch officials at an airport in The Netherlands.
They have been charged with four counts of crimes against humanity and one of war crimes committed by Serbian death squads in Bosnia and Croatia after the break-up of the former Yugoslavia in 1991.
UN prosecutors, who had called for life sentences in the original trial, accuse the pair of organising, financing and supplying Serb paramilitary groups between April 1991 and the end of 1995.
The units cut a swathe of terror and destruction across Croatia and Bosnia as they attacked towns and murdered Croats, Muslims and other non-Serbs to force them out of large areas seeking to create a Serb-run state, prosecutors said.
More than 100,000 people died and millions of others were left homeless in the 1992-95 conflict, which saw some of the worst atrocities on European soil since World War II.
In May 2013, the judges ruled the prosecution had failed to prove "beyond reasonable doubt" that the pair had planned or ordered the crimes and acquitted them.
But in a rare turnabout, the appeals court in December 2015 quashed the acquittals.
It said the original trial bench had "erred" on several points of law.
The five-judge appeals bench also made the unusual decision not to impose new sentences, but ordered the men to be tried again on all counts. Their first trial lasted from June 2009 to January 2013.
Monday's ruling could set off a new showdown with Serbia, which since January 2015 has refused the tribunal's orders to arrest three other Serbian officials accused of witness tampering.