San Diego is to the left, Tijuana to the right (click to enlarge)
UPDATE
This scenario reminds me of the movie, Act of Valor, via USA Today:
The U.N. nuclear agency says a truck carrying an extremely dangerous radioactive substance has been stolen in Mexico.
The International Atomic Energy Agency says the truck was carrying cobalt-60, used for radiotherapy treatment to combat cancer. An IAEA statement Wednesday said the truck was stolen Monday while taking the material to a radioactive waste storage center from the northern city of Tijuana.