[Girlene]

Perhaps authorities realize they don’t have a clear picture of his background.

Doesn't sound like they do. Still, they are throwing a lot of rescources at finding him.

It appears he joined the Marines in September, 2004, prior to his marriage in 2005. As sopdoodle said, you can't become a citizen through marriage. So I'm wondering if he was already a citizen prior to joining.

[Brian S. Fitzgerald]

The FBI Charlotte office now has the info:

Nationality: Mexican

I see no mention that he is a US Citizen.

http://charlotte.fbi.gov/pressrel/2008/ce011308.htm