Oh No ! Who is there ?

Went back to the same spot this afternoon. Found a surprised visitor (Yes, I was sure they were as surprised to see me as I was to see them) :


Oh No, Who is that ?


Went on to find a closer look :



Wow. Must be running out of places for them to conduct training. Hope I did not stumble upon some secret equipment. If you do not hear from me the next few days, you know where I am....