Those strong enough to go on will usually travel only at night, hiding by day under mesquite brush to avoid the sun and the spotter aircraft of the Border Patrol.

ECONOMIST: Illegal immigration: Worth dying for | The

You do your day's graft at work, and at night you go to bed and you're exhausted by the morning because all night you've just done a patrol or whatever.

BBC: Iraq 10 years on: The human cost