The trial of Bosnian Serb Ratko Mladic, which was set to start June 25, has been "suspended until further notice" the UN War Crimes Tribunal for the former Yugoslavia said according to The AP.
Mladic was arrested on May 16, 2011 after 16 years on the run, The Jerusalem Post reports.
According to The Financial Times, he is being charged with 11 counts of war crimes and crimes against humanity including genocide for allegedly overseeing the massacre of 8,000 Muslim men and boys in Srebrenica, Bosnia in 1995.
The court's decision to suspend the trial is a result of the prosecution's error in disclosing documents to the defense, BBC News reports.
The trial began on May 16, but judges granted the defense another month to gather evidence, The AP reports.
In a statement Monday, the court said they would publish a full decision in "due course."
Mladic, 70, is the last key figure wanted for war crimes during the Bosnian War, BBC News reports.
Relatives of the victims worry that if the trial takes too long, Mladic, who suffers from heart problems, may die before a verdict is reached, Reuters reports.
Slobodan Milosevic died in 2006 before a judgment was issued in his war crimes trial for the Balkans war.