[ZOTnot]

If one does report suspicions, does anything happen? Do they acknowledge?

What if one is in a capital city, and people with cameras appear to be innocently photographing 'architecture' or 'historical sites'?

[STARWISE]

Call the FBI closest office and tell them. They are under no obligation and generally WOULD NOT EVER follow up with you. Our job is to help them by reporting suspicious events/people .. their job is to follow up on tips and to keep US safe. They owe us no answer or follow-up. I've done it several times when situations warranted. I never received nor expected a follow-up from them .. that's a waste of their time.

You're doing your public duty to report something like the photo taking .. no matter how innocent it may seem, if it strikes you as odd and is synch with our known enemies, just do it .. you never know what you may be preventing. Our crime fighters just can't be everywhere all the time.