In CAMP BUCCA, Iraq the inmates huddle below the barbed wire, looking up at the strangers who have arrived at the detention facility. They're dressed in bright yellow, almost fluorescent jumpsuits. There are 2,000 of them, described by the U.S. military as hard-core al Qaeda loyalists. These inmates are kept behind a maze of chain-link fences, topped with barbed wire, and are guarded by heavily armed men in military fatigues who hold shields. We're escorted through Camp Bucca, the United States' biggest detention facility in Iraq, by Marine Gen. Douglas Stone, who runs the camp. "They're hard to break," he says of the suspected al Qaeda inmates. As Stone speaks, some inmates begin pointing up and we're told to keep moving. We wear protective glasses to cover our eyes. Inmates here throw rocks from the dusty, gravel floor at visitors, sometimes using makeshift slingshots to hurl the pebbles at 100 mph. Several guards have been blinded by the projectiles. Walk along with Nic Robertson through the facility » "This is not a place you want to hang around, so we really don't want to stand here that much longer because they will organize around us," Stone says. We press on through the facility. As we record our television piece, we're not allowed to talk to the inmates or show their faces -- doing so would be in violation of the Geneva Conventions. Inside Camp Bucca, the al Qaeda loyalists make up a minority of more than 19,000 civilian detainees. They are neither criminals nor prisoners of war. They are detained because they are deemed a security threat, many accused of taking up arms against American soldiers