A bus stopped at a highway checkpoint in Mexico's northern Tampaulipas state was found to be carrying more than just passengers on Tuesday. Gamma-ray equipment detected 43 packages hidden in the internal structure of the bus containing a total of US$981,140 (S$1.3 million). This was seized by the Mexican military and handed over to the Attorney-General's Office. The driver, his assistant and the vehicle were also taken into custody. The bus had been heading south to San Fernando, from Reynosa, a city bordering Texas, at the time. Mexico's drug cartels have been known to use buses to smuggle their products to the United States border and carry the proceeds from sales.