A row of headlights shines south into the darkness.
Stop!
Minuteman sees the three shapes head north against the headlights. He
lets them pass. The boys’ll take care of them. That’s what back-up is
for. Another two dash back across, toward the darkness. Fuckers. He
heads into the gulch after them. They scramble up the bank on all
fours. He’s past the flat of the river bed, they’re almost to the top.
Now or never. He shoots.
Just a kid.
Panic hits. Mexican side. No time. He grabs at the boy trying to get a
grip. His hands slip on the blood. The boy isn’t cooperating. Don’t
die, don’t die. Hang in there. Heavier than he looks. He loses his
grip. Let’s go, let’s go.
It’s brighter now. A lone pair of headlights now shines the other way
across the river. Minuteman drags the boy down the slope, toward the
lights on the north bank. He sees the others against the headlights.
Why are they standing there?
¡Alto!
Minuteman tries to run, but the boy’s arm catches in his legs. He
trips, still on the downslope. A car door opens and shuts. No one
moves, not Minuteman, not the boy, not the figures against the
headlights on the far slope. A voice speaks into a radio. Footsteps
approach from above.

Very evocative work!
What a vivid scene. I read it twice.
Thanks for reading.
I also want to say that i always appreciate your time and effort in leaving comments, ganymeder & cubehermit.