Hidden bridge

So, when I took the camera off my bag, a "very suspect person" appear from nowhere, and come to my direction, I saw it from the corner off my eye, took some pictures and put the camera back in the bag, so I turn an walk to another dude ho was taking pics too and raise my hand as I knew him, them the "Very Suspect Person" turn around and walk away.. the other photographer did'nt even notice anything... hehe