My gut has told me from the beginning that this has something to do with Fast & Furious. An old bud was killed by one of OUR guns?
I think a link to F & F may be a stretch. There was no “need” for him to acquire weapons illegally.
Now, if they came back to the US and were sold either privately or at a gun shop, that would be something the Feds would want to keep a lid on.
Still doesn’t provide a motive.
As the week has played out I’m leaning more and more to an Islam connection.