Rwandan genocide
In October 1993, the United Nations Security Council created the United Nations Assistance Mission for Rwanda (UNAMIR).  It was supposed to help put the 1993 peace agreement into place.  However, UNAMIR did not have permission from the Security Council to protect civilians or try to stop the genocide.  At this time, UNAMIR soldiers were only allowed to shoot their weapons in self-defence, if somebody was attacking them personally.  They were not allowed to use their weapons or get involved to protect civilians who were being attacked.