After 9-11 the FBI can do almost anything they want and it be considered legal. I am not debating if that is right or wrong, just saying that when something falls under national security or terrorism, they get a really long leash.
Why did they run into the woods if they were doing nothing wrong? Where exactly were they going to "train" and who with. (need names and phone numbers) I think we all go shooting a fair bit, but how many of us go across several states to do it? That all falls under the feds to investigate.
The "heavily" armed thing was a little blown out of proportion I think. They did not even have one fire arm per person. I mean me and my wife have taken that amount to the range several times. We however do not stand along the road with rifles in hand like this is Mexico or the middle east or some other crap hole.
The story is weird and a little blown out of proportion. Very weird though. For sure these guys are retards and need to learn to respect the law they do not recognize.