So, the guy pulled a dumb and didn't check his bag thoroughly from a trip the previous year. And made it through TSA screening in the States prior to leaving.
Yay, TSA. Great job, folks. Anyway...
Also didn't have the accompanying weapon to the ammo... so, not seeing the hubbub here.
I have this feeling there is a lot more being unsaid in this case. If he acted the fool with the customs people at his destination, I could see the problem here and him getting locked up.
I'm gonna give that a "probably happened" label.
Now, if they are just going overboard over a box of ammo, that's a little extreme.
I'm gonna give that a "maybe" label.
Hypothetically speaking, if he went the dumb American route, was calm and explained "hey, went on a trip last year, didn't realize it was still in the bag, I'm dumb for not checking and please allow me to surrender it and accept whatever fine you feel is appropriate for said dumb act. May I please do what's necessary to get back to my family?" that might have worked.
However...
If he pulled the indignant role, played Mister Tough Guy American That's Better Than You Third World People and went overboard, that's a different story and probably needs to be sitting in that jail while a determination is made.
I have this feeling the truth is somewhere is the middle. But I'm leaning towards "dumb American tough guy" that ran his mouth.