The Mexican navy has seized 38 tons of chemicals used to make synthetic drugs such as crystal meth.
The chemicals arrived in the Pacific port of Manzanillo aboard a ship that sailed from Shanghai, China.
The substance had been declared in customs as benzyl salicylate, but lab tests identified it as ethyl phenylacetate, a chemical that must undergo special checking to be allowed into the country.
Stored in two tanks, the chemical was headed for the Mexican capital. With this confiscation, authorities have now nabbed 590 tons of drug precursors since December 2006.
The port of Manzanillo is one of the most frequently used points of entry for drugs and where some of the biggest drug busts have taken place.
In 2007 more than 23.5 tons of cocaine were seized in that terminal, and in 2008 close to $13 million in cash were intercepted from trade operations between Mexican and Colombian cartels.