A combined army and police force on patrol in the northern Mexican state of Sinaloa has dismantled three labs producing the synthetic drug methamphetamine.
Officials estimated the labs could produce 17 million doses of meth.
They said their discovery was the biggest blow to meth trafficking so far this year.
Crystal meth is a powerful form of amphetamine and can be smoked, snorted or injected by users.
The discovery raises the number of drug labs detected in Sinaloa state to 20 this year.
The illegal substances are smuggled across the border into the US, which is the world's largest consumer of drugs.
Most of the methamphetamine available in the United States is produced clandestinely in Mexico, according to the US Drug Enforcement Administration (DEA).
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Sinaloa's security minister, Cristóbal Castañeda Camarillo, said in this case the discovery was made by agents patrolling the rural area on foot.
But an increasing number of drug labs has been located by drones fitted with heat detectors, officials said.
Sinaloa state, in the north-west of Mexico, has long been dominated by the criminal cartel by the same name.
Its former leader, Joaquín "El Chapo" Guzmán, has been convicted by a US court for drug trafficking and is due to be sentenced later this month.
Despite the arrest of "El Chapo" in 2016, his Sinaloa cartel has the greatest drug trafficking impact on the US, according to the DEA.
As well as producing methamphetamine, it also smuggles marijuana, cocaine, heroin, and fentanyl into the US and has well-established distribution hubs in Phoenix, Los Angeles, Denver, and Chicago.