The survey estimated that about 14m people had used illegal drugs, and 600, 000 had smoked crack cocaine, in the month before the survey, the same figures found by the survey a decade earlier.

ECONOMIST: Prisoners

At the entrance to a local primary school, a group of four men sat and smoked what appeared to be crack cocaine, what locals call "piedra" or rock.

WSJ: Mexico's Drug Cartels May Have Become Too Powerful to Control