A container of Iridium-192, a radioactive material used in construction and manufacturing, was stolen from a supplier’s vehicle in a borough outside of Mexico City. There have been a number of similar thefts in Mexico in the past few years and, while most of the materials have been recovered, they have raised fears of “dirty bomb” risks from terrorists within the U.S. 

Source: Radioactive material stolen from vehicle in Mexico City | Montreal Gazette