SACRAMENTO, Calif. (KTXL) — As more people are getting vaccinated and venues and events open back up, some people are trying to sell forged vaccination documents.

Vaccination cards are likely going to become a big part of life for Americans as communities recover from the COVID-19 pandemic.

As all Californians become eligible for the COVID-19 vaccination on April 15, indoor events will start to require proof of vaccination or a negative test.

The FBI issued a warning Monday that it is illegal to sell or buy fraudulent COVID-19 vaccination cards after fake vaccination cards have begun popping up for sale online.

“There are some people that just don’t want to get vaccinated, but they still want to go to the baseball game and they still want to travel internationally, and so this might appeal to them,” explained Don Vilfer, the president of Digital Evidence Ventures and former FBI agent.

Vilfer told FOX40 that getting a fake vaccination card can land people in serious trouble.

“It’s a federal crime here in the US. It’s also fraud and could be charged under forgery,” Vilfer said.

He also warned people that giving the information that needs to go on the card to someone who is already breaking the law is a bad idea.

“It doesn’t make very good sense to me to provide personal information, maybe your date of birth, your name, address for the card, along with your credit card information to somebody you know to be a scammer already who’s preparing a forged document for you,” Vilfer said.

By the time a vaccination card needs to be checked for travel or events, Vilfer said that process will already have gone digital.

“Regulatory agencies, government agencies, TSA for example, have access to that database and can verify your information pre-flight,” Vilfer said.

FOX40 was informed that the World Health Organization is already working with an app called Common Pass which allows international passengers to prove their vaccination to foreign governments.

However, not all countries have agreed to it yet.