i said, i -- i was just angry, and i was just incredulous, so to speak. and the tree that we were underneath was on fire. >> but the attack isn't over. and the biggest explosion is yet to come. manning a machine gun at the checkpoint is specialist darrell green. >> at that time, they -- the cement mixer was trying to come through our perimeter. >> a huge cement mixer filled with explosives tries to sneak through the breach made by the first blast and drive up to the hotels. >> their main goal with the first two explosions was to make a hole into our perimeter, which the first explosion did. the second vehicle was deterred and went into a different direction. >> guards opened fire on the cement truck using everything they have to prevent it from getting close enough to kill hundreds. >> once the dust settled, i engaged that vehicle before it got to the hotel and subsequently stopped the driver from making it in between the two hotels. >> the truck backs up as