Kabul, Afghanistan (CNN) The boy was left for nearly 20 hours before the ambulance could reach him. He was unable to move because a bullet had torn a hole through his abdomen. When the fighting finally subsided, he was driven the 130 kilometers north from Ghazni to Kabul and a specialized hospital that treats the war-wounded.

The boy, 12, became one of 50 cases the Italian nongovernmental organization Emergency treats on a daily basis in what has become the surgical center's busiest year on record.

At the entrance to the children's ward, a whiteboard lists the injuries: shrapnel, mine, shrapnel, shrapnel, mine, shrapnel, bullet, bullet, bullet, shrapnel, shotgun, bullet, shrapnel, bullet, bullet, bullet, bullet. Children account for about 30% of all patients the hospital treats.

Doctors begin another round of surgery on a teen who had his arm torn off by a bomb. Surgeons say his is an average case.

The center treats victims from across the country, but in recent months, it's been the increasing violence in and around the capital that has affected even the most hardened staff members.

"Even Kabul is not secure. When I'm coming from home and I say hello to my baby and wife, I am thinking sometimes there is no guarantee to be back at home," says Najibullah Hekmat, a third-generation Afghan surgeon trained and working at the hospital.

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