In the darkness of an early morning in Iraq, a convoy of 70-ton tanks and armored Humvees rumbles around Baghdad and beyond.

Iraqi spies, supplied with digital cameras, global-positioning systems (search) and laptop computers, have identified enemy suspects believed to be selling improvised explosive devices. Paid informants sometimes "talk" to their U.S. military handlers through Yahoo! chat rooms on the Internet, relaying critical information that targets alleged bomb makers.

"We think that they are actually orchestrating the attacks and moving arms and munitions to plant IEDs (search) ... build IEDs and coordinate the attacks," said Lt. Col. Randy Lane, commander of the U.S. Army's Task Force 135.

In the past seven weeks alone, U.S. officers say more than 120 homemade bombs have gone off around Baghdad. Soldiers have various names for the bomb builders — "bonehead" is the nicest.

But sometimes a tip turns out to be a fluke.

As much beat cops as they are professional soldiers, the troops take notes, check stories and routinely search for explosive residue on the hands of men who stumble into military roadblocks. Military officials say so-called precision "house-by-house" raids are now the norm when going after specific targets.

Those rounded up are taken to a holding facility. The U.S. military says about half are released without being slapped with any charges, while the other half is held longer if they're suspected of making and selling munitions.

"It's a hindrance for some of the locals but we also inform them that it is for their safety. Most of them cooperate very well," said Capt. Christopher Hormann, Alpha Company, 2nd battalion 6th infantry.

Go to the video box at the top of this story to watch a report by Fox News' Orlando Salinas.