Freight train in subway

Exactly that: I saw a freight train, loaded with cars of industrial equipment (?), pass through a subway station.   

 It was not preceded by an announcement, and no notices were posted.

 Completely unexplained. I like it, though.

This post's theme word is pharate (adj.), "(of an adult insect) Waiting to emerge from a cocoon" or "(of an animal, especially an insect) in transition between stages of development." The pharate equipment slithered through the subway tunnels en route to its mysterious final destination.