 "The group belly-crawled to a sand berm," according to a UN report released in March 2012, and then through two drainage pipes and set up a defensive position.One of Gaddafi's guards threw a grenade at advancing rebels on the road above, but it hit a concrete wall above the pipes and fell in front of Gaddafi.The guard tried to pick it up, but it exploded, killing both the guard and Yunis Jabr.