"Papers seized in the battle implicated Leonard Pierce Jr., the United States consul in Matamoros, as an instigator of the raid."

Joe, do you have a source (book, web site) that one can look at for the "Papers" you mention?

I'm interested in the fact that one could go into Mexico, a sovereign nation to run down anyone, without permission from that Country. Was there an agreement between the Confederacy and Mexico at the time for such measures?
Respectfully:

Kevin Dally