Mexico, Mexico City - Mexico's government said Thursday it had seized 14 million doses of fentanyl, the latest major haul in a drive to stem the flow of the powerful opioid into the US.

The Public Security ministry said the drugs were found during raids on a clandestine drug laboratory and warehouse in the municipality of Villa de Alvarez in violence-hit western Colima state.

At the warehouse, police found "approximately 270 kilograms (595 lbs.) of a substance with characteristics similar to fentanyl, both in powder and pill form," which the ministry said was equivalent to about 14 million doses.

It said six people were arrested, but did not say when the operation took place, nor give the estimated street value of the drugs.

It was not a record for fentanyl hauls, officials told AFP, pointing to a 2024 operation that yielded a ton more of the drug.

The raids come as President Donald Trump ramps up his criticism of Mexico's record on fighting drug trafficking, despite the recent capture and killing of a notorious drug lord.

At a summit with right-wing Latin American leaders in Florida last weekend, where he launched a 17-country Americas Counter Cartel Coalition, Trump declared that cartels were "running Mexico" and vowed to "eradicate them."

In December, he classified fentanyl, a powerful painkiller responsible for tens of thousands of overdose deaths in the US each year, as a "weapon of mass destruction," placing it in the same category as nuclear and chemical weapons.

Mexico's left-wing President Claudia Sheinbaum argues that US weapons are fueling cartel activities and called on Washington to halt the flow of guns south across the border.