(Bloomberg) -- People who tried to order medicine online or over the phone have received fake U.S. Food and Drug Administration warning letters instead of the products they bought, in what appears to be an international extortion scam, the agency said on Friday.

In the past few weeks, the FDA has received more than three dozen notifications about the letters from consumers.

The letters were designed to look legitimate. Two samples provided by the agency showed that the senders used the official FDA logo and correct address. One letter also claimed to be from the U.S. Federal Trade Commission. However, the writing in the letters contained shaky grammar and odd word choices.

Two of the letters said consumers had violated several sections of the Federal Food, Drug, and Cosmetic Act. They then asked addressees to notify the FDA “of the specific steps that you have taken to correct those violations.” The issuers said not to contact the seller and threatened “necessary legal steps” should they find out about “any suspicious activity from your end.”

“Consumers who aren’t involved in manufacturing or distributing FDA regulated products should be on alert that if you get an FDA warning letter, it’s probably fake, and probably a scam,” the agency’s commissioner, Scott Gottlieb, said in a statement. The agency said it generally does not take action against individuals for purchasing medicine online. Instead, the FDA would target the owners and operators of any illegal websites.

First Fakes

The ploy is the first time the agency has seen a scam involving fake warning letters, said Lyndsay Meyer, a spokeswoman for the agency. Sending out warning notifications to consumers is an otherwise common tool for the FDA to alert people about potential harm.

In the meantime, the FDA recommends consumers only buy medications online from U.S.-licensed pharmacies that require a prescription and notify the agency should they receive a fake warning letter.

A 2015 report by the National Association of Boards of Pharmacy that reviewed close to 11,000 websites selling prescription medications found that about 96 percent of those websites were not compliant with U.S. laws and patient-safety standards.

To contact the reporter on this story: Aziza Kasumov in New York at akasumov@bloomberg.net

To contact the editors responsible for this story: Drew Armstrong at darmstrong17@bloomberg.net, Timothy Annett, Cecile Daurat

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