I think the story about the phone call from unidentified mexican is a cover story. They needed to get this story out but not panick anyone so they invented the mexican mule.
I agree....they got this info from another source.
I think you might be right. The Mexican tip is a cover to protect a source.
"I think the story about the phone call from unidentified mexican is a cover story. They needed to get this story out but not panick anyone so they invented the mexican mule."
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I think you are right. There seems to be much more to this.