Mexico's Federal Commission for the Protection against Health Risks (COFEPRIS) has warned that selling counterfeit Pfizer vaccines poses a "health risk" to the population.
Earlier this week, Pfizer said it had identified counterfeit Covid-19 shots in Mexico and Poland.
Responding to the reports, COFEPRIS said:
"Any alleged vaccine against Covid-19 that is for sale through internet pages, social media, by telephone, pharmacies, hospitals, and points of sale, constitutes fraud and a health risk because it's of doubtful origin."
The commission has warned of fake Pfizer-BioNTech Covid-19 vaccines in the Mexican state of Nuevo Leon in February.
Vaccination against Covid-19 is free and universal in Mexico, COFEPRIS said in the statement, adding that it hasn't issued a license to any company for the sale or import of the vaccines.
"Any unauthorized vaccination report is alarming since it's illegal, irregular, and puts the health of those who receive it at risk," it said.
"People can trust that all the vaccines from the National Vaccination Program against Covid-19 are of quality, safe and effective since they were approved by this commission."