THE HAGUE, June 8 (Reuters) -- United Nations war crimes judges on Tuesday upheld a genocide conviction and life sentence against former Bosnian Serb military commander Ratko Mladic, confirming his central role in Europe’s worst atrocities since World War Two. Mladic, 78, led Bosnian Serb forces during Bosnia’s 1992-95 war. He was convicted in 2017 on charges of genocide, crimes against humanity and war crimes including terrorising the civilian population of the Bosnian capital Sarajevo during a 43-month siege, and the killing of more than 8,000 Muslim men and boys in the eastern Bosnian town of Srebrenica in 1995.