As the flarelight sputtered away, Horton crawled to the gully side. He looked up. He saw the flashing barrel of a gunman silhouetted against the 4WD's headlights. Pushing in his Ithaca's safety, he put the shotgun's front sight on the center of the gunman's chest, and squeezed the trigger.

The man dropped. Horton slid down as burst after burst searched for him. A grenade flashed, throwing dirt and chopped mesquite over him. Butterfield crawled to him. Horton gave him commands in a hiss.

"Keep moving! That way. Dump the sand out of that barrel before you try to fire it."

Butterfield tried to speak, but could not. Horton shoved him on as bullets puffed dust only an arm's length above them.

A form jumped into the gully. Horton lay still, watching the darkness, his shotgun on line.

Light bathed the brush and rocks. Horton saw a shoulder and the side of a head above a tangle, twenty yards away. He sighted, and he waited.

The gunman raised his M-16. Horton fired a blast of Number Six birdshot into the man's face.

Screaming, his face and part of a hand gone, the gunman thrashed in the dust. Blood sprayed from his destroyed mouth as he called out in Spanish to the others.

Horton pumped his weapon to chamber another round, and waited for the flarelight to give him another target.

The air above him exploded with shrapnel and slugs. A heavy-caliber machine gun hammered at the gully, the dirt exploding with the impacts of slugs and grenade blasts.

Behind Horton, Butterfield fired his shotgun once, twice. Then a tight-throated whine became a scream as an autoburst raked Butterfield's legs. Horton scrambled as he saw a form with a flashing muzzle.

Raising his shotgun, Horton fired at the same instant as his target, hundreds of tiny lead balls racing to kill the gunman even as a 40mm fragmentation grenade struck only inches from Horton's feet.