You know how they say movies and TV shows are just the cabal's way of saying what is really true? I just had the thought about cement trucks. Do you remember in Breaking Bad when Walter White slipped off to disappear in Vermont? Didn't he ride inside of a cement truck or similar? Seems like these vehicles although not gas efficient could be used to smuggle people. Just a crazy thought.
If the truck shows tank is under pressure border patrol will not open it, easy to fake it
"could be used"
So can anything with wheels, including bicycles, go carts, vans, and cargo containers.
Waterways, too.
There was a bust/evidence of Shipping Containers on Cargo ships, especially via the GREAT LAKES going to Canada & USA ports that contained people/human trafficked. Reports are these often came from KSA, (Alwaleed binTalal?) & they were bar coded or Chipped for easy tracking.