Intl--->Intl Connection at MEX
I am flying from IAH to MEX on United then onward to FRA on Lufthansa. The flights are on separate itineraries. A couple of questions. If I can convince UA in IAH to check the bags through to FRA on LH will I have to recheck them in MEX. Given both airlines are in Terminal 1 will I also have to go through immigration and pass through security?