In 1995 the situation in UN Safe Areas was deteriorating, and it led to a diplomatic crisis which culminated in the Srebrenica massacre; one of the worst atrocities in Europe since World War II. The UN Resolution 819 and 836 had designated Srebrenica a "safe area" to be protected using "all necessary means, including the use of force". Continued attacks on UN Safe Areas as well as the continued Siege of Sarajevo also ultimately resulted in NATO intervention in Bosnia and Herzegovina named Operation Deliberate Force.