MEXICO CITY -- The Mexican army has seized a cache of over 926 tons (840 metric tons) of precursor chemicals used to make methamphetamines, one of the largest such seizures to date in Mexico.
The discovery came Wednesday, the same day an army patrol in another location found a sophisticated underground meth lab reachable by a 35-yard (meter) long tunnel.
Mexico has become a center for meth production, based on precursor chemical shipped in from foreign suppliers, often in Asia.
The Defense Department said soldiers found thousands of sacks of phenylacetamide in a warehouse in the north-central state of Queretaro.
Photos from the scene of the raid showed the phenylacetamide stacked several yards (meters) high, and hundreds of drums of other chemicals also used to make meth.
In 2010 authorities seized 200 tons of precursor chemicals at the seaport of Manzanillo, a bust the Attorney General's Office described at the time as the largest in Mexican history.
Traffickers have increasingly turned to such chemicals after Mexico imposed tight restrictions on pseudoephedrine, the most popular raw ingredient for meth.
In the northern state of Sinaloa, meanwhile, the army said soldiers found a sophisticated underground meth lab in a rural area near the coastal city of Mazatlan.
Construction was apparently continuing on the structure, which included a 1 1/2-yard wide entrance tunnel, a power generator, three large mixing chambers and a welding machine.
Watch BBC's report on the underground drug lab here: