RAMADI, Iraq —  U.S. Army combat engineers based in Ramadi (search) began their day by blowing up two unexploded mortars — one of which they pulled from the body of a fellow soldier.

From that grim mission, they began their next — patrolling the streets of Ramadi, looking for improvised explosive devices. But the first IED found them instead. Shrapnel from a roadside bomb exploded next to U.S. armored humvees but injured no one. It was detonated by a satellite phone in the hands of a nearby insurgent.

Minutes later, just a few feet away, combat engineers found a second bomb -- this one so large, if a humvee — even a fully armored one — had run over it, it would have been what the engineers call a "catastrophic kill."

Further down the road, the engineers found a weapons store -- a hole filled with mortars, a rocket-propelled grenade launcher, a propane tank packed with explosives and disassembled AK-47s. The soldiers dug up the store and detonated everything in it.

IEDs are the No. 1 killer of military personnel in this area of Iraq. Finding them and blowing them up is dangerous but critical work.

Click on the video box above for a complete report by FOX News' Caroline Shively.