Bosnian Serb troops massacred some 8,000 Bosnian Muslim men and boys after taking over the UN-protected safe haven of Srebrenica in July 1995. Some 30,000 women, children and the elderly were also expelled from the enclave and their homes.
Dutch UN peacekeepers had surrendered the enclave to the Bosnian Serbs, who were under the command of General Ratko Mladic, without firing a shot.
Ruling on a Bosnian lawsuit against Serbia, the UN International Court of Justice (ICJ) said in 2007 that atrocities at Srebrenica were committed with the intention of destroying the Muslim population there and were therefore acts of genocide.
It cleared Serbia of direct responsibility for the act, though it did say that Serbia should have done more to prevent the atrocity and bring perpetrators to justice. The verdict disappointed Muslims in the region.
The UN International Criminal Tribunal for the former Yugoslavia (ICTY) has so far delivered three final convictions for genocide at Srebrenica, plus two for aiding and abetting.
Two other guilty rulings, against wartime Bosnian Serb political leader Radovan Karadzic and the commander of Serb armed forces Ratko Mladic, have been handed down in the first instance.
Karadzic was sentenced to 40 years in jail on March 26, 2016 and his case is under appeal.
On November 22, Mladic was sentenced to life for genocide and other war crimes, and is also appealing.
Both cases will be brought to a conclusion under a legal process due to take over from ICTY, which will close at the end of 2017.
In 2009, the European Parliament declared July 11 to be a day of remembrance for victims of the biggest war crime in Europe since World War II.
