GRAFTON, Wis. (CBS) — A Wisconsin hospital worker has been fired for intentionally removing COVID-19 vaccine from a refrigerator – forcing the hospital to throw out more than 500 doses.

Aurora Medical Center – Grafton, outside Milwaukee, said 57 vials of Moderna vaccine were taken out of a pharmacy refrigerator and left overnight.

The hospital launched an investigation and was led to believe inadvertent human error was to blame. But on Wednesday, the worker who was responsible admitted to doing it on purpose, Advocate Aurora Health said.

The hospital has notified authorities to investigate.

“We continue to believe that vaccination is our way out of the pandemic. We are more than disappointed that this individual’s actions will result in a delay of more than 500 people receiving their vaccine,” Advocate Aurora Health said in a statement. “This was a violation of our core values, and the individual is no longer employed by us.”

Grafton police said “no comment” when CBS 2’s Marissa Parra called and asked if they were involved or investigating.

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