Two families from the mainland U.S. have been charged with trying to use counterfeit COVID-19 vaccine papers to enter Hawaii.

Prosecutors say one of the families was visiting from California, the other from Florida when they allegedly tried to pass off the fake vaccination cards. Airport screeners tipped off police to the couple from Miami, who also tried to use fake vaccine cards for their young children.

The office of Hawaii’s Attorney General praised the airport security team for spotting the fake documentation.

“The Department of the Attorney General works collaboratively with other governmental partners to keep Hawaii safe from COVID and will investigate and prosecute those attempting to dishonestly bypass the Safe Travels program.”

Office of Hawaii Attorney General

The couple from the Los Angeles area were caught after police received an anonymous tip.

Demand for counterfeit vaccine cards is growing as some anti-vaccine people turn to illegal methods to avoid the restrictions they face for not getting inoculated. As a result, law enforcement is stepping up its efforts to keep those fake cards from making it onto the black market. Customs agents recently intercepted thousands of phony cards meant to be sold in various U.S. cities.

In Hawaii, The use of falsified documents for travel is a misdemeanor. Violators face penalties of up to a $5,000 fine and/or up to one year in prison. Hawaii is the only state enforcing proof of vaccination to enter.