Steven Brandenburg removed 57 vials of the Moderna COVID-19 vaccine, each containing around 10 doses, from refrigerators at the Aurora Medical Center in Grafton, Wisconsin, in an attempt to destroy them because he believed — wrongly — that they were dangerous and could alter human DNA.

The Moderna and Pfizer-BioNTech vaccines are based on mRNA technology that delivers genetic information to the human body to help produce antibodies against the coronavirus. Experts say there is no evidence at all to suggest they alter human DNA, and millions have been inoculated using these vaccines.

They require very low temperatures for storage and can be damaged or destroyed otherwise, which is what Brandenburg tried to do on two occasions, the prosecution said Monday during his first court appearance.

"His intent ... was to render them inert because he'd formed this belief that they were unsafe, that the RNA method of creating these medications rendered them unsafe," Ozaukee County district attorney Adam Gerol said during the hearing.

Brandenburg had initially told hospital authorities that the vaccines were left unrefrigerated by accident, but later admitted that he removed them on purpose.

The 46-year-old also admitted on one occasion to putting the unrefrigerated vaccines back inside, which were later injected into 57 people, the hospital's operator said.