(TNS) — Fraudulent COVID-19 vaccination cards are being sold online, and authorities have warned individuals not to buy or make one — which is illegal.

"Be aware of individuals selling fake COVID-19 vaccination record cards and encouraging others to print fake cards at home," the FBI said in a public service announcement last week. "Fake vaccination record cards have been advertised on social media websites, as well as e-commerce platforms and blogs."

Vaccine providers issue individuals a vaccination card after they are immunized against the coronavirus. The cards, usually issued by the Centers for Disease Control and Prevention, contain an individual's personal information, like name, birth date and which vaccine a person received.

The National Association of Attorneys General on Thursday sent a letter to the CEOs of Twitter, eBay and Shopify to "act immediately to prevent" the selling of fake vaccination cards on their websites. "We are deeply concerned about this use of your platforms to spread false and misleading information regarding COVID vaccines," says letter, signed by more than 40 officials including acting California Attorney General Matthew Rodriquez. "The false and deceptive marketing and sales of fake COVID vaccine cards threatens the health of our communities, slows progress in getting our residents protected from the virus, and are a violation of the laws of many states."

The association asked the companies to carefully monitor their platforms, remove ads or links that are selling fake cards and to take note of the ads and individuals who are selling them.

The FBI also urged the public to not post photos of their vaccine cards to their social media.

"Your personal information could be stolen to commit fraud," the FBI said.

The FBI's alert comes a month after the Federal Trade Comission warned that photos of a vaccination card can lead to identity theft. If individuals want to share that they've been vaccinated, the agency recommended sharing a photo of their adhesive bandage or "I got my COVID-19 vaccine!" sticker.

A spokesman for Shopify on Sunday said selling COVID-19 vaccination cards on its platform is a violation of company policies.

"We have been proactively monitoring our platform for the sale of COVID vaccine cards since February, and all stores that we identified for violating our policies were actioned swiftly," Vivek Narayanadas, Shopify's vice president of legal and data protection officer, said in a statement.

Parmita Choudhury, a spokeswoman for eBay, said Sunday that the company has been blocking or removing items from its marketplace, including vaccination cards, that falsely claim a person has been vaccinated. Since December, it has removed or blocked 50 million listings that have violated company policies related to COVID-19, she said.

"eBay is also working closely with the FDA to monitor for listings related to COVID vaccines," Choudhury said in a statement.

A Twitter representative said Sunday a response to a Chronicle request for information was in the works.

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