A United Nations war crimes appeals court on Thursday acquitted Momcilo Perisic, the former chief of staff for the Yugoslav army, of all charges and ordered his immediate release, DPA reported.
In 2011, a UN tribunal for the former Yugoslavia found Perisic guilty of war crimes and crimes against humanity for his role in atrocities committed during the Balkan wars of the 1990s - including the massacre at Srebrenica - and gave him a 27-year jail sentence.
The Hague-based appeals court ruled that the 65-year-old's guilt had not been proven beyond a reasonable doubt.
Serbian Prime Minister Ivica Dacic welcomed the verdict, saying it disproves accusations that the former Yugoslav army had committed acts of aggression against Bosnia.
The genocide trial of former Serbian leader Slobodan Milosevic at the same tribunal ended without a verdict when he died of a heart attack in 2006 while in detention.