I don't know anything about the strange truck you are describing but I saw a strange one yesterday. It had no markings anywhere on it other than a
big yellow sign on the back that said "SUICIDE" and had an arrow pointing to the right side. It creeped me out.
Actually the suicide thing is something you see on a lot of big rig trailers, especially double trailers.
The full thing says "Passing side" with an arrow pointing to the left and "Suicide" with an arrow pointing to the right, basically letting you
know that if you pass the truck on the right there's a good chance you won't be seen by the driver and there's a good chance you're gonna get
packed like a can o' peaches.
The truck you're describing sounds like a nuclear waste transporting truck. Was it an enclosed semi or was it a flatbed with a huge silver cylinder
in the center chained down? If it's that second one then it's a nuclear waste transporter.
They always have police protection because of anti-nuclear energy groups trying to blow up the trailer or something. Release everything into the
atmostphere or bury it underground for 10,000 years away from everything else? Well obviously the protest groups don't really care about what
they're protesting, they just want to get a point across regardless of what the point really is.