Updated at 7:08 p.m. ET

The Wisconsin pharmacist accused of intentionally sabotaging more than 500 doses of the coronavirus vaccine at Christmastime told police he did it because he believed the drug is somehow hazardous.

"He'd formed this belief they were unsafe," Ozaukee County District Attorney Adam Gerol said of Steven Brandenburg on Monday during a virtual hearing, The Associated Press reported.

Gerol did not offer more information on why Brandenburg was convinced the inoculations could be harmful, but he did paint a picture of a troubled man in the midst of personal turmoil. He explained that the 46-year-old is in the process of divorcing his wife, and he said a fellow Advocate Aurora Health employee reported that Brandenburg had taken a gun to work twice.

Brandenburg, who worked as a pharmacist with the Advocate Aurora Health hospital system, has admitted he deliberately removed 57 vials of the Moderna vaccine from refrigeration and left them out overnight on Dec. 24 and again on Dec. 25. After leaving them out at room temperature overnight on Christmas Eve, Brandenburg returned the vials to their proper storage. But after he pulled them out the second night, they were discovered by a pharmacy technician.

Wisconsin Public Radio reports Gerol couldn't submit proof to the court that the drugs had been damaged and that therefore a crime had been committed.

"And apparently the only way they can discover that or tell us that is if they test them. It's unknown how much time that will take," Gerol said, according to the outlet.

The Moderna vials must be stored between 36 and 46 degrees Fahrenheit. They can remain effective for up to 12 hours if left at room temperature. Beyond that, the drugmaker says, the vaccine is no longer effective.

Regardless, there is a crime known as attempted criminal damage to property, Gerol said, and that "would be a misdemeanor and that would seem to apply at some point in time in the future."

Brandenburg has since been fired after the incident.

As a result of Brandenburg's tampering, health care workers were forced to discard about 570 doses of the potentially lifesaving vaccine. Hospital officials said 57 individuals did receive injections of what may have been useless doses. Those patients have been notified and are not at any risk of adverse health effects, hospital officials said on Friday. The pharmacist last week told investigators he knew "that people who received the vaccinations would think they had been vaccinated against the virus when in fact they were not," officials said.

Brandenburg was arrested on Thursday by the Grafton Police Department on recommended charges of first-degree recklessly endangering safety, adulterating a prescription drug and criminal damage to property. The FBI and U.S. Food and Drug Administration are also investigating.

The AP reported: "Judge Paul Malloy set a $10,000 signature bond for Brandenburg and ordered him to surrender all his firearms to sheriff's deputies, not to work in the health care field and to have no contact with Aurora employees."

Brandenburg was released on Monday afternoon.

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