Three Vermont state troopers have resigned after being accused of making fake COVID-19 vaccination cards, prompting a federal investigation, authorities announced this week.

The now-former troopers Shawn Sommers, Raymond Witkowski and David Pfindel recently handed in their badges after fellow troopers became aware of the alleged scheme and reported their behavior internally, the Vermont State Police (VSP) said Tuesday.

The three men are suspected of “having varying roles” in the cards’ creation, authorities said in a statement that did not go into further detail.

Col. Matthew T. Birmingham, director of the Vermont State Police, said he “could not be more upset and disappointed” by the allegations that, in his words, “tarnished the reputation of the Vermont State Police.”

“If these allegations are proved to be true, it is reprehensible that state troopers would manipulate vaccination cards in the midst of a pandemic, when being vaccinated is one of the most important steps anyone can take to keep their community safe from COVID-19,” he said in a statement.

Sommers and Witkowski, who both joined the police force in 2016, resigned shortly after concerns were raised internally last month about their alleged conduct. Pfindel, who was hired in 2014, resigned on Friday after an investigation by the state’s Department of Public Safety was completed, state police said.

Vermont Public Safety Commissioner Michael Schirling said his office’s investigation concluded that nothing more could have been done to prevent the troopers’ actions from occurring.

“As soon as other troopers became aware of this situation, they raised the allegations internally, and commanders took swift and decisive action to hold these individuals accountable and report this matter to federal authorities,” he said in a statement.

Buying, selling or using a counterfeit COVID-19 vaccination card that features an official government agency seal, such as the one featured on authentic vaccination cards, can result in a fine and up to five years in prison, the Federal Bureau of Investigation has warned following the discovered use and manufacture of such cards across the country.

Due to the seriousness of the allegations against the troopers, the case was presented to the U.S. Attorney’s Office in Burlington and the FBI for review. News of the allegations had not been publicly released until this week due to the FBI’s ongoing investigation, state police said. 

Vermont Gov. Phil Scott (R) last month announced that some state workers would be required to get vaccinated after coronavirus cases began rising in the state due to the delta variant. Employees who didn’t would face regular testing. Scott announced at a press conference Wednesday that this vaccine requirement will be expanded to all state executive branch employees.

Sommers, Witkowski and Pfindel were not part of this initial group that was required by the state to be vaccinated, VSP Public Information Officer Adam Silverman told HuffPost on Wednesday. Silverman referred any additional questions about the troopers’ vaccine requirements to the governor’s office, which did not immediately respond to a request for comment. A representative with the Vermont Troopers’ Association, which represents troopers, detectives and sergeants of the VSP, also did not not immediately respond to a request for comment.

Vermont, as a state, boasts the nation’s highest rate of total vaccine doses fully administered per 100,000 people, according to the Centers for Disease Control and Prevention. As of this week, about 77% of vaccine-eligible Vermonters, age 12 and older, have been fully vaccinated against the virus, according to figures provided by the state’s health department.