From BBC News:
Mexican soldiers have destroyed four “narco-tanks”, lorries fitted with steel armour thought to have been made for the Gulf drug cartel. The vehicles were seized in a garage in Camargo, in the northeastern state of Tamaulipas. Authorities said the cartel used the tanks, fitted with air-conditioning and steel plates, to patrol its smuggling routes and transport drugs to the US. Two of the tanks had already been fitted with armour 2.5cm (1in) thick. Two more lorries were in the process of being fitted with steel plates, and 23 articulated lorries were still awaiting modification.