I looked and did not see a previous post on this but may have missed it? Anyways, here is a link that now says that the two Americans were CIA anti drug people, etc, etc.
Americans wounded in Mexico 'were CIA employees' - Yahoo! News
Some things I noted while watching the local Mexican news channel with my free over the air HD coverage was that the side windows stopped the bullets BUT they went through the rear window, very large holes there! A quick shot of the interior showed bullets had gone through the sheet metal in the side doors and there were holes in the front seats! Finally the cameraman, crafty that he was, got a real closeup of a couple of shell cases and they were NOT 5.56, looked like steel case 7.62x39 so they did not seem to be shot at by the US armed people with AR-15s? Seems the news has been very quiet on this for some reason..........hummmmm