The laminated cards feature an image of an eagle and say "Face Mask Exempt Card" in bold letters across the top.
They appear to be geared toward people trying to skirt state and business requirements to wear face masks in public, or to receive service.
The card also references the DOJ and the Americans with Disabilities Act.
But Freedom to Breathe Agency, the group that posted them on its website and distributed the cards, isn't a federal or state agency. It's a Facebook group that says on its website it's trying to stop face mask orders "from spreading nationwide and globally."
Its founder, Lenka Koloma, told CNN it wasn't making any recommendations to anyone and the group's mission is "freedom and personal liberty." But she went on to say that people should only wear masks, "whenever they wish to be silenced and muzzled."
The DOJ's Civil Rights division and a US Attorney's office have now posted warnings about the cards, calling them fraudulent.
"Do not be fooled by the chicanery and misappropriation of the DOJ eagle," Matthew G.T. Martin, US attorney for the Middle District of North Carolina, said in a news release. "These cards do not carry the force of law. The 'Freedom to Breathe Agency,' or 'FTBA,' is not a government agency."
The warning comes as the number of Covid-19 cases continues to rise across the United States. Some 60% of states have seen increases in coronavirus cases in the last week.
Scientific research continues to show that mask wearing is saving lives by helping prevent the spread of Covid-19 by infected and asymptomatic people.
The US Centers for Disease Control and Prevention has urged people to wear them since early April.
Still, Koloma and her group are pushing falsehoods -- including that mask wearing dangerously limits oxygen. According to its Facebook page, the group had over 5,500 members.
It's unclear if the cards were presented anywhere by anyone.
There are multiple versions of the main card, including specific ones for Colorado and California.
"I am exempt from any ordinance requiring face mask usage in public," one of the cards says. "Wearing a face mask poses a mental and/or physical risk to me."
The cards also give the impression of being issued by an official government agency.
"Denying access to your business/organization will also be reported to FTBA for further actions," it reads, in all capital letters, at the bottom.
Some of the cards were even made to look more official, bearing the seal of the Department of Justice.
Koloma and Fred DiDomenico, who are listed as the co-administrators of the Facebook group, confirmed to CNN the group distributed the cards with the DOJ seal. Koloma and DiDomenico would not say why the cards had the DOJ seal on them or why they removed them.
The group disappeared from Facebook on Thursday afternoon. Koloma provided CNN with a screenshot with a notification saying Facebook removed the group for "fraud and deception."
Prior to its removal, CNN had reached out to Facebook for comment about the group. CNN has not received a response to the initial inquiry or to a follow-up inquiry about why the group's page was removed.
The group's website, created and hosted by Wix, also disappeared from the internet Wednesday morning. Koloma says they are unsure why it disappeared.
Wix has not responded to a request for comment.
Koloma says although the group was asking for donations on the site, it was not taking in any money. She has since created a new group page on Facebook and says it plans to distribute new cards.